Android Programming: what changed

Revision 4 to 5. Removed lines have a minus sign; added lines have a plus sign.

Old	New		Line
1	1		(Android only)
2	2
3	3		See also [[Custom Drawn Interface/Android]]
4	4
5	5		Knowing general Android programming can be very useful to help develop the Lazarus Android Interface.
6	6
7	7		## Platform Tips
8	8
9	9		## How to...
10	10
11	11		### Build the NDK OpenGL example
12	12
13	13		Just follow these steps:
14	14
15	15		Step 1 - Download and install the Android NDK, Android SDK and Ant. More information here: [[Android Interface/Using the Android SDK, Emulator and Phones\|Android_Interface/Using_the_Android_SDK%2C_Emulator_and_Phones]]
16	16
17	17		Step 2 - Install the pre-compiled FPC cross-compiler. Instructions here: [[Android Interface\|Android_Interface#Using_the_pre-compiled_compiler]]
18	18
19	19		Step 3 - Download the latest lazarus-ccr sourceforge code:
20	20
21	21		``` bash
22	22		svn co https://lazarus-ccr.svn.sourceforge.net/svnroot/lazarus-ccr lazarus-ccr
23	23		```
24	24
25	25		or if you think it is too big you can download just the folder lazarus-ccr/bindings/android-ndk
26	26
27	27		Step 4 - Building the Pascal Library
28	28
29	29		> Note: In the steps below, the directory /home/felipe/Programas or ~/Programas is used. Please adjust if your paths are different.
30	30
31	31		Open the project lazarus-ccr/bindings/android-ndk/examples/opengltest/opengltest.lpi
32	32
33	33		Go to Project-\>Project Options-\>Paths and where is written "Libraries -Fl" you should see a value like this:
34	34
35	35		```text
36	36		/home/felipe/Programas/android-ndk-r5/platforms/android-9/arch-arm/usr/lib
37	37		```
38	38
39	39		Change it to the correct path in your system which points to the NDK and to the library folder for your minimal required Android API Level
40	40
41	41		Now build the project using Lazarus.
42	42
43	43		Step 5 - Configuring the build environment
44	44
45	45		Open the file opengltest/local.properties. Change this line to point to your SDK location:
46	46
47	47		```text
48	48		sdk.dir=/home/felipe/Programas/android-sdk-linux
49	49		```
50	50
51	51		Step 6 - Buildings the APK
52	52
53	53		Open a terminal and type these commands:
54	54
55	55		``` bash
56	56		cd lazarus-ccr/bindings/ndk/examples/opengltest/android
57	57		ant debug
58	58		```
59	59
60	60		The APK file will be placed in opengltest/android/bin/
61	61
62	62		Step 7 - Install the APK
63	63
64	64		In this step, if you get error messages about permissions read: [[Android Interface/Using the Android SDK, Emulator and Phones\|Android_Interface/Using_the_Android_SDK%2C_Emulator_and_Phones#Recognition_of_devices_under_Linux]]
65	65
66	66		The command to install our APK in the phone is:
67	67
68	68		``` bash
69	69		cd opengltest/android
70	70		~/Programas/android-sdk-linux/platform-tools/adb install bin/OpenGLNDKTest-debug.apk
71	71		```
72	72
73	73		You should see something like:
74	74
75	75		```text
76	76		2395 KB/s (107299 bytes in 0.043s)
77	77		pkg: /data/local/tmp/OpenGLNDKTest-debug.apk
78	78		Success
79	79		```
80	80
81	81		If you get an error message that it is already installed you can install with this command:
82	82
83	83		``` bash
84	84		~/Programas/android-sdk-linux/platform-tools/adb uninstall com.pascal.opengltest
85	85		```
86	86
87	87		And then you can run adb logcat to see what the log says while you start it in the phone via its newly added icon:
88	88
89	89		``` bash
90	90		~/Programas/android-sdk-linux/platform-tools/adb logcat
91	91		```
92	92
93	93		### Read the screen metrics
94	94
95	95		First fill a TDisplayMetrics with the correct info:
96	96
97	97		``` pascal
98	98		uses androidutil;
99	99
100	100		var
101	101		MyDisplayMetrics: TDisplayMetrics;
102	102		Str: string;
103	103		//
104	104		lHeight, lWidth: Integer;
105	105		xdpi, ydpi, lScreenSize: Single;
106	106		begin
107	107		// ..
108	108		// Objects
109	109
110	110		MyDisplayMetrics := TDisplayMetrics.Create;
111	111		Activity.getWindowManager().getDefaultDisplay().getMetrics(MyDisplayMetrics);
112	112		```
113	113
114	114		And then you can read it from the TDisplayMetrics:
115	115
116	116		``` pascal
117	117		lHeight := MyDisplayMetrics.heightPixels();
118	118		lWidth := MyDisplayMetrics.widthPixels();
119	119		xdpi := MyDisplayMetrics.xdpi();
120	120		ydpi := MyDisplayMetrics.ydpi();
121	121		lScreenSize := sqrt(sqr(lHeight / ydpi) + sqr(lWidth / xdpi));
122	122		ldensity := MyDisplayMetrics.density();
123	123		ldensityDpi := MyDisplayMetrics.densityDpi();
124	124		scaledDensity := MyDisplayMetrics.scaledDensity();
125	125		```
126	126
127	127		Note that lots of devices lie about the xdpi and ydpi, so don't trust the lScreenSize calculated above. Smartphones might report even 10 inches of screen size, while the correct is around 4.
128	128
129	129		## Details about Android devices
130	130
131	131		Since there are so many Android devices, it can be useful to keep track of some information about them. See also in the wikipedia Comparison of Android Devices [1](http://en.wikipedia.org/wiki/Comparison_of_Android_devices) and details about the processors in [2](https://wiki.mozilla.org/Mobile/Platforms/Android#System_Requirements).
132	132
133	133		### Smartphones
134	134
135	135		\| Manufacturer \| Model \| Android API Name (Build.Model) \| Processor \| Android version \| Multi-touch \| Comments \|
136	136		\|----\|----\|----\|----\|----\|----\|----\|
137	137		\| HTC \| Wildfire \| HTC Wildfire \| armv6 \| 2.1=\>2.2 \| Yes\\|\\|- \| \|
138	138		\| Sony Erricson \| Xperia X10 \| X10i \| armv7 \| 1.6=\>2.1 \| No\\|\\|- \| \|
139	139
140	140		### Tablets
141	141
142	142		\| Manufacturer \| Model \| Android API Name (Build.Model) \| Processor \| Android version \| Multi-touch \| Comments \|
143	143		\|----\|----\|----\|----\|----\|----\|----\|
144	144		\| Toshiba \| Folio 100 Tablet \| TOSHIBA_FOLIO_AND_A \| armv7 \| 2.2 \| Yes\\|\\|- \| \|
145	145
146	146		### List of devices ordered by processor compatibility (ARMv6 vs ARMv7)
147	147
148		-	~~<caption>List of ARMv7 devices</caption>~~
149		-	~~<tbody>~~
150		-
151		-	~~Fascinate, Vibrant, Epic 4G)</td>~~
	148	+	List of ARMv7 devices
152	149
153		-	~~</tbody>~~
	150	+	\| Advent Vega (P10AN01) \| Dell Streak, Streak 7 \| HTC Desire \| HTC Desire Z (T-Mobile G2) \| HTC Desire HD \|
	151	+	\|---\|---\|---\|---\|---\|
	152	+	\| HTC Droid Incredible \| HTC EVO 4G, EVO Shift 4G \| HTC Glacier (T-Mobile myTouch 4G) \| HTC Inspire 4G \| HTC Nexus One \|
	153	+	\| HTC Thunderbolt 4G \| Huawei Ideos S7 \| LG Optimus Z \| Motorola Atrix 4G \| Motorola Bravo \|
	154	+	\| Motorola Cliq 2 - untested \| Motorola Defy \| Motorola Droid 2, Droid 2 Global \| Motorola Droid Pro (Motorola Pro) \| Motorola Droid X \|
	155	+	\| Motorola Xoom \| POV Mobii Tegra Tablet \| Samsung Continuum (i400) \| Samsung Galaxy S (i9000, Captivate, · Fascinate, Vibrant, Epic 4G) \| Samsung Galaxy Tab \|
	156	+	\| Sharp IS03 \| Sony Ericsson Xperia X10 \| Toshiba AS100 \| Viewsonic gTablet \| Acer Liquid E \|
	157	+	\| Acer Liquid (Liquid A1) \| Archos 101 Internet Tablet \| Motorola Charm \| Motorola Droid (Milestone) \| Samsung Galaxy S 4G \|
	158	+	\| Samsung Nexus S \| \| \| \| \|
154	159
155	160		\| \| \| \| \|
156	161		\|----\|----\|----\|----\|
157	162		\| Android SDK emulator \| Asus Garmin nuvifone A50 (T-Mobile Garminfone) \| Augen GENTouch 78 Tablet \| Coby Kyros Internet Tablet (MID7015) \|
158	163		\| Geeksphone One, Geeksphone Zero \| HTC Aria \| HTC ChaCha \| HTC Dream (T-Mobile G1, Android Dev Phone 1) \|
159	164		\| HTC Droid Eris \| HTC Espresso (T-Mobile myTouch 3G Slide) \| HTC Hero (T-Mobile G2 Touch) \| \\|HTC Legend \|
160	165		\| HTC Magic (T-Mobile myTouch 3G, T-Mobile G1 Touch) \| HTC Salsa \| HTC Tattoo \| HTC Wildfire \|
161	166		\| Huawei Ascend \| Huawei Ideos U8150-B (T-Mobile Comet) \| Huawei U8110 (T-Mobile Pulse Mini) \| \\|Huawei U8230 \|
162	167		\| LG Ally (Apex) (LG VS740) \| LG GW620 (Eve, InTouch Max, LinkMe) \| LG Optimus, Optimus M, Optimus T, Optimus S, Optimus V \| LG Vortex \|
163	168		\| LG P500 \| MAG iMiTO iM7 \| vMAG iMiTO iM7S \| Motorola Backflip \|
164	169		\| Motorola Citrus \| Motorola Cliq (MB200) \| Motorola Dext \| Motorola Devour \|
165	170		\| Motorola i1 \| Motorola Spice XT300 \| Motorola Quench XT5 XT502 \| Pandigital Novel \|
166	171		\| Samsung GT-S5570 Galaxy Mini \| Samsung i5500 Galaxy 5 (Corby) \| Samsung i5700 Galaxy Portal (Spica) \| Samsung i5800 Galaxy 3 \|
167	172		\| Samsung i7500 Galaxy \| Samsung Intercept \| Samsung M900 Moment \| Samsung S5830 Galaxy Ace \|
168	173		\| Samsung Transform \| Sanyo ZIO M6000 \| Sony Ericsson Xperia X8 \| Sony Ericsson Xperia X10 Mini \|
169	174		\| Sony Ericsson Xperia X10 Mini Pro \| Superpad 10.2" Tablet PC \| Viewsonic ViewPad 7 Tablet \| Velocity Micro T103 Cruz tablet \|
170	175		\| Vodafone 845 \| ZTE Blade \| \| \|
171	176
172	177		List of ARMv6 processors:'''
173	178
174	179		### Playing sounds and videos on the phones
175	180
176	181		Each phone comes with different codecs installed, which means that the native Media Player will be able to play different formats in different phones. Below is a table showing which formats play in the native Media Player of each phone:
177	182
178	183		\| Telephone \| Android \| webm - VP8 \| m4v - H.264 \| ogv - Theora \| mp4 - H.264 \| mov - H.264 \| avi - RLE \| mpg - MPEG-1 \| wmv - WM9 \| 3gp - MPEG-4 \|
179	184		\|----\|----\|----\|----\|----\|----\|----\|----\|----\|----\|----\|
180	185		\| Emulator \| 1.6 \| x \| x \| x \| x \| x \| x \| x \| x \| OK \|
181	186		\| Emulator \| 2.1 \| x \| x \| x \| x \| x \| x \| x \| x \| OK \|
182	187		\| Nexus One \| 2.2 \| x \| OK \| x \| OK \| x \| x \| x \| x \| OK \|
183	188		\| HTC Desire \| 1.6 \| x \| OK \| x \| OK \| x \| x \| x \| OK \| OK \|
184	189		\| Toshiba Folio 100 \| 2.2 \| x \| OK \| x \| OK \| x \| x \| x \| OK \| OK \|
185	190		\| Xperia X10 \| 2.1 \| x \| OK \| x \| x \| x \| x \| x \| OK \| OK \|
186	191		\| Xperia X8 \| 2.2 \| x \| OK \| x \| x \| x \| x \| x \| x \| OK \|
187	192		\| HTC Wildfire \| 2.1 \| x \| OK \| x \| x \| x \| x \| x \| x \| OK \|
188	193		\| HTC Desire HD \| 2.2 \| x \| OK \| x \| OK \| x \| x \| x \| x \| OK \|
189	194		\| Galaxy Tab \| 2.2 \| x \| OK \| x \| x \| x \| x \| x \| x \| OK \|
190	195		\| myPhone A210 \| 1.6 \| x \| OK \| x \| x \| x \| x \| x \| x \| OK \|
191	196		\| Motorola Milestone \| 2.1 \| x \| OK \| x \| x \| x \| x \| x \| OK \| ? \|
192	197		\| Milestone 2 \| 2.2 \| x \| OK \| x \| x \| x \| x \| x \| sound-only \| OK \|
193	198
194	199		## Android file system
195	200
196	201		Android recommends to use getApplicationContext().getFilesDir() to obtain the data directory for the application and this routine in my HTC Wildfire returns /data/data/\<package name\>
197	202
198	203		The native libraries of the application are placed in /data/data/\<package\>/lib
199	204
200	205		A good place where we have read and write access and we can create new files and even run files is /data/data/\<package name\>
201	206
202	207		## Creating a new Java Android application
203	208
204	209		This info can be useful for helping implement LCL-CustomDrawn-Android
205	210
206	211		Generic instructions here: <http://developer.android.com/guide/developing/other-ide.html>
207	212
208	213		### Showing/hiding the virtual keyboard
209	214
210	215		See here: <http://android-codes-examples.blogspot.com/2011/11/show-or-hide-soft-keyboard-on-opening.html>
211	216
212	217		To show it:
213	218
214	219		``` java
215	220		InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
216	221		imm.toggleSoftInput(InputMethodManager.SHOW_FORCED,0);
217	222		```
218	223
219	224		and for hiding the keyboard:
220	225
221	226		``` java
222	227		InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
223	228		imm.hideSoftInputFromWindow(singleedittext.getWindowToken(),0);
224	229		```
225	230
226	231		## Android JNI
227	232
228	233		Using JNI (Java Native Interface) you can call most Android SDK APIs and also other Java libraries.
229	234
230	235		### Table of Java types and Pascal JNI types
231	236
232	237		All of the Java types except interfaces can be represented in JNI without problems. For each Java type there is a corresponding VM Type Signature which is utilized in routines such as javaEnvRef^^.GetMethodID. There is also the JNI native type, which is the type declared in the unit lazarus/lcl/interfaces/customdrawn/android/jni.pas and should be the type utilized in JNI code written in Pascal. The Pascal equivalent is provided just for comparison, as one should use the types from jni.pas when writing JNI code.
233	238
234	239		\| Java type \| VM signature \| Type in jni.pas \| Pascal equivalent \| Description \|
235	240		\|----\|----\|----\|----\|----\|
236	241		\| boolean \| Z \| jboolean \| Boolean \| \|
237	242		\| byte \| B \| jbyte \| Byte \| \|
238	243		\| char \| C \| jchar \| Word \| \|
239	244		\| short \| S \| jshort \| Shortint \| \|
240	245		\| int \| I \| jint \| Integer \| \|
241	246		\| long \| J \| jlong \| Int64 \| \|
242	247		\| float \| F \| jfloat \| Single \| \|
243	248		\| double \| D \| jdouble \| Double \| \|
244	249		\| a class, ie: String or InputStream \| L\<full class name\> ie: Ljava/lang/String; \| jobject \| N/A \| \|
245	250		\| Array, ie: int\[\] \| \[\<type-name\> ie: \[I \| N/A \| \| \|
246	251		\| A method type \| (arg-types)ref-type \| JMethodID \| N/A \| \|
247	252		\| void \| V \| N/A \| procedure \| \|
248	253
249	254		### Example 1: Creating a Java object and calling a Java method
250	255
251	256		Let's say that you want to make Pascal JNI code equivalent to the following Java code:
252	257
253	258		``` java
254	259		HttpGet javaRequest = new HttpGet();
255	260		URI myURI = new URI("http://magnifier.sourceforge.net/");
256	261		javaRequest.setURI(myURI);
257	262		```
258	263
259	264		First you need to get all Class IDs involved in the process, then get all method IDs which we will use and then make the calls. If the call has parameters, then pass it in an array. The following Pascal native code is equivalent to that Java code above:
260	265
261	266		``` pascal
262	267		uses jni, customdrawnint;
263	268
264	269		var
265	270		javaClass_HttpGet, javaClass_URI: jclass;
266	271		javaMethod_HttpGet_new, javaMethod_HttpGet_setURI,
267	272		javaMethod_URI_new: jmethodid;
268	273		javaRequest, javaURI: jobject;
269	274		javaString: jstring;
270	275		lParams: array[0..2] of JValue;
271	276		lNativeString: PChar;
272	277		begin
273	278		DebugLn(':>LoadHTMLPageViaJNI');
274	279		// First call FindClass for all required classes
275	280		javaClass_HttpGet := javaEnvRef^^.FindClass(javaEnvRef,
276	281		'org/apache/http/client/methods/HttpGet');
277	282		javaClass_URI := javaEnvRef^^.FindClass(javaEnvRef,
278	283		'java/net/URI');
279	284
280	285		// Now all Method IDs
281	286		DebugLn(':LoadHTMLPageViaJNI 1');
282	287		javaMethod_HttpGet_new := javaEnvRef^^.GetMethodID(javaEnvRef, javaClass_HttpGet, '<init>', '()V');
283	288		javaMethod_HttpGet_setURI := javaEnvRef^^.GetMethodID(javaEnvRef, javaClass_HttpGet, 'setURI', '(Ljava/net/URI;)V');
284	289		javaMethod_URI_new := javaEnvRef^^.GetMethodID(javaEnvRef, javaClass_URI, '<init>', '(Ljava/lang/String;)V');
285	290
286	291		// Create a new instance for the HTTP request object
287	292		// HttpGet javaRequest = new HttpGet();
288	293		javaRequest := javaEnvRef^^.NewObject(javaEnvRef,
289	294		javaClass_HttpGet,
290	295		javaMethod_HttpGet_new);
291	296
292	297		DebugLn(':LoadHTMLPageViaJNI 4 javaRequest='+IntToHex(PtrInt(javaRequest), 8));
293	298		// Add a URI for the request object
294	299		// URI javaURI = new URI("http://magnifier.sourceforge.net/");
295	300		lParams[0].l := javaEnvRef^^.NewStringUTF(javaEnvRef, 'http://magnifier.sourceforge.net');
296	301		javaURI := javaEnvRef^^.NewObjectA(javaEnvRef,
297	302		javaClass_URI, javaMethod_URI_new, @lParams[0]);
298	303		javaEnvRef^^.DeleteLocalRef(javaEnvRef, lParams[0].l);
299	304		// javaRequest.setURI(javaURI);
300	305		lParams[0].l := javaURI;
301	306		javaEnvRef^^.CallVoidMethodA(javaEnvRef, javaRequest,
302	307		javaMethod_HttpGet_setURI, @lParams[0]);
303	308		```
304	309
305	310		### Example 2: Calling a static method
306	311
307	312		Let's say that you want to call the following static method located in the Bass class: <http://jerome.jouvie.free.fr/nativebass/javadoc/org/jouvieje/bass/Bass.html>
308	313
309	314		``` java
310	315		public static native int BASS_StreamCreateFile(String file, long offset, long length, int flags);
311	316		```
312	317
313	318		First you need to get all Class IDs involved in the process, then get the static method ID and then make the call with the parameter in the array:
314	319
315	320		``` pascal
316	321		uses jni, customdrawnint;
317	322
318	323		var
319	324		javaClass_Bass: jclass;
320	325		javaMethod_Bass_BASS_StreamCreateFile: jmethodid;
321	326		javaString: jstring;
322	327		lParams: array[0..3] of JValue;
323	328		lRetInt: jint;
324	329		begin
325	330		// First call FindClass for all required classes
326	331		javaClass_Bass := javaEnvRef^^.FindClass(javaEnvRef, 'org/jouvieje/bass/Bass');
327	332
328	333		// Now all Method IDs
329	334		javaMethod_Bass_BASS_StreamCreateFile := javaEnvRef^^.GetStaticMethodID(javaEnvRef, javaClass_Bass, 'BASS_StreamCreateFile', '(Ljava/lang/String;JJI)I');
330	335
331	336		// Make the call
332	337		lParams[0].l := javaEnvRef^^.NewStringUTF(javaEnvRef, '/path/to/file');
333	338		lParams[1].j := 0; // offset
334	339		lParams[2].j := 200; // length
335	340		lParams[3].i := 0; // flags
336	341		lRetInt := javaEnvRef^^.CallStaticIntMethodA(javaEnvRef, javaClass_Bass, javaMethod_Bass_BASS_StreamCreateFile, @lParams[0]);
337	342		javaEnvRef^^.DeleteLocalRef(javaEnvRef, lParams[0].l);
338	343		```
339	344
340	345		## References
341	346
342	347		- <http://developer.android.com/guide/developing/other-ide.html>
343	348		- [Tutorial "Lazarus and Android"](https://dl.dropboxusercontent.com/u/3753548/Lazarus%20and%20Android.pdf) (PDF file)
344	349
345	350		---
346	351		From the Free Pascal wiki, page "Android Programming", as it stood on 2019-12-16 after a change by Trev, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).

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