Android Programming: what changed

Revision 2 to 3. 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		-	~~`/home/felipe/Programas/android-ndk-r5/platforms/android-9/arch-arm/usr/lib`~~
	35	+	```
	36	+	/home/felipe/Programas/android-ndk-r5/platforms/android-9/arch-arm/usr/lib
	37	+	```
36	38
37	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
38	40
39	41		Now build the project using Lazarus.
40	42
41	43		Step 5 - Configuring the build environment
42	44
43	45		Open the file opengltest/local.properties. Change this line to point to your SDK location:
44	46
45		-	~~`sdk.dir=/home/felipe/Programas/android-sdk-linux`~~
	47	+	```
	48	+	sdk.dir=/home/felipe/Programas/android-sdk-linux
	49	+	```
46	50
47	51		Step 6 - Buildings the APK
48	52
49	53		Open a terminal and type these commands:
50	54
51	55		``` bash
52	56		cd lazarus-ccr/bindings/ndk/examples/opengltest/android
53	57		ant debug
54	58		```
55	59
56	60		The APK file will be placed in opengltest/android/bin/
57	61
58	62		Step 7 - Install the APK
59	63
60	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]]
61	65
62	66		The command to install our APK in the phone is:
63	67
64	68		``` bash
65	69		cd opengltest/android
66	70		~/Programas/android-sdk-linux/platform-tools/adb install bin/OpenGLNDKTest-debug.apk
67	71		```
68	72
69	73		You should see something like:
70	74
71		-	~~`2395 KB/s (107299 bytes in 0.043s)`\~~
72		-	~~` pkg: /data/local/tmp/OpenGLNDKTest-debug.apk`\~~
73		-	~~`Success`~~
	75	+	```
	76	+	2395 KB/s (107299 bytes in 0.043s)
	77	+	pkg: /data/local/tmp/OpenGLNDKTest-debug.apk
	78	+	Success
	79	+	```
74	80
75	81		If you get an error message that it is already installed you can install with this command:
76	82
77	83		``` bash
78	84		~/Programas/android-sdk-linux/platform-tools/adb uninstall com.pascal.opengltest
79	85		```
80	86
81	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:
82	88
83	89		``` bash
84	90		~/Programas/android-sdk-linux/platform-tools/adb logcat
85	91		```
86	92
87	93		### Read the screen metrics
88	94
89	95		First fill a TDisplayMetrics with the correct info:
90	96
91	97		``` pascal
92	98		uses androidutil;
93	99
94	100		var
95	101		MyDisplayMetrics: TDisplayMetrics;
96	102		Str: string;
97	103		//
98	104		lHeight, lWidth: Integer;
99	105		xdpi, ydpi, lScreenSize: Single;
100	106		begin
101	107		// ..
102	108		// Objects
103	109
104	110		MyDisplayMetrics := TDisplayMetrics.Create;
105	111		Activity.getWindowManager().getDefaultDisplay().getMetrics(MyDisplayMetrics);
106	112		```
107	113
108	114		And then you can read it from the TDisplayMetrics:
109	115
110	116		``` pascal
111	117		lHeight := MyDisplayMetrics.heightPixels();
112	118		lWidth := MyDisplayMetrics.widthPixels();
113	119		xdpi := MyDisplayMetrics.xdpi();
114	120		ydpi := MyDisplayMetrics.ydpi();
115	121		lScreenSize := sqrt(sqr(lHeight / ydpi) + sqr(lWidth / xdpi));
116	122		ldensity := MyDisplayMetrics.density();
117	123		ldensityDpi := MyDisplayMetrics.densityDpi();
118	124		scaledDensity := MyDisplayMetrics.scaledDensity();
119	125		```
120	126
121	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.
122	128
123	129		## Details about Android devices
124	130
125	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).
126	132
127	133		### Smartphones
128	134
129	135		\| Manufacturer \| Model \| Android API Name (Build.Model) \| Processor \| Android version \| Multi-touch \| Comments \|
130	136		\|----\|----\|----\|----\|----\|----\|----\|
131	137		\| HTC \| Wildfire \| HTC Wildfire \| armv6 \| 2.1=\>2.2 \| Yes\\|\\|- \| \|
132	138		\| Sony Erricson \| Xperia X10 \| X10i \| armv7 \| 1.6=\>2.1 \| No\\|\\|- \| \|
133	139
134	140		### Tablets
135	141
136	142		\| Manufacturer \| Model \| Android API Name (Build.Model) \| Processor \| Android version \| Multi-touch \| Comments \|
137	143		\|----\|----\|----\|----\|----\|----\|----\|
138	144		\| Toshiba \| Folio 100 Tablet \| TOSHIBA_FOLIO_AND_A \| armv7 \| 2.2 \| Yes\\|\\|- \| \|
139	145
140	146		### List of devices ordered by processor compatibility (ARMv6 vs ARMv7)
141	147
142	148		<caption>List of ARMv7 devices</caption>
143	149		<tbody>
144	150
145	151		Fascinate, Vibrant, Epic 4G)</td>
146	152
147	153		</tbody>
148	154
149	155		\| \| \| \| \|
150	156		\|----\|----\|----\|----\|
151	157		\| Android SDK emulator \| Asus Garmin nuvifone A50 (T-Mobile Garminfone) \| Augen GENTouch 78 Tablet \| Coby Kyros Internet Tablet (MID7015) \|
152	158		\| Geeksphone One, Geeksphone Zero \| HTC Aria \| HTC ChaCha \| HTC Dream (T-Mobile G1, Android Dev Phone 1) \|
153	159		\| HTC Droid Eris \| HTC Espresso (T-Mobile myTouch 3G Slide) \| HTC Hero (T-Mobile G2 Touch) \| \\|HTC Legend \|
154	160		\| HTC Magic (T-Mobile myTouch 3G, T-Mobile G1 Touch) \| HTC Salsa \| HTC Tattoo \| HTC Wildfire \|
155	161		\| Huawei Ascend \| Huawei Ideos U8150-B (T-Mobile Comet) \| Huawei U8110 (T-Mobile Pulse Mini) \| \\|Huawei U8230 \|
156	162		\| LG Ally (Apex) (LG VS740) \| LG GW620 (Eve, InTouch Max, LinkMe) \| LG Optimus, Optimus M, Optimus T, Optimus S, Optimus V \| LG Vortex \|
157	163		\| LG P500 \| MAG iMiTO iM7 \| vMAG iMiTO iM7S \| Motorola Backflip \|
158	164		\| Motorola Citrus \| Motorola Cliq (MB200) \| Motorola Dext \| Motorola Devour \|
159	165		\| Motorola i1 \| Motorola Spice XT300 \| Motorola Quench XT5 XT502 \| Pandigital Novel \|
160	166		\| Samsung GT-S5570 Galaxy Mini \| Samsung i5500 Galaxy 5 (Corby) \| Samsung i5700 Galaxy Portal (Spica) \| Samsung i5800 Galaxy 3 \|
161	167		\| Samsung i7500 Galaxy \| Samsung Intercept \| Samsung M900 Moment \| Samsung S5830 Galaxy Ace \|
162	168		\| Samsung Transform \| Sanyo ZIO M6000 \| Sony Ericsson Xperia X8 \| Sony Ericsson Xperia X10 Mini \|
163	169		\| Sony Ericsson Xperia X10 Mini Pro \| Superpad 10.2" Tablet PC \| Viewsonic ViewPad 7 Tablet \| Velocity Micro T103 Cruz tablet \|
164	170		\| Vodafone 845 \| ZTE Blade \| \| \|
165	171
166	172		List of ARMv6 processors:'''
167	173
168	174		### Playing sounds and videos on the phones
169	175
170	176		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:
171	177
172	178		\| 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 \|
173	179		\|----\|----\|----\|----\|----\|----\|----\|----\|----\|----\|----\|
174	180		\| Emulator \| 1.6 \| x \| x \| x \| x \| x \| x \| x \| x \| OK \|
175	181		\| Emulator \| 2.1 \| x \| x \| x \| x \| x \| x \| x \| x \| OK \|
176	182		\| Nexus One \| 2.2 \| x \| OK \| x \| OK \| x \| x \| x \| x \| OK \|
177	183		\| HTC Desire \| 1.6 \| x \| OK \| x \| OK \| x \| x \| x \| OK \| OK \|
178	184		\| Toshiba Folio 100 \| 2.2 \| x \| OK \| x \| OK \| x \| x \| x \| OK \| OK \|
179	185		\| Xperia X10 \| 2.1 \| x \| OK \| x \| x \| x \| x \| x \| OK \| OK \|
180	186		\| Xperia X8 \| 2.2 \| x \| OK \| x \| x \| x \| x \| x \| x \| OK \|
181	187		\| HTC Wildfire \| 2.1 \| x \| OK \| x \| x \| x \| x \| x \| x \| OK \|
182	188		\| HTC Desire HD \| 2.2 \| x \| OK \| x \| OK \| x \| x \| x \| x \| OK \|
183	189		\| Galaxy Tab \| 2.2 \| x \| OK \| x \| x \| x \| x \| x \| x \| OK \|
184	190		\| myPhone A210 \| 1.6 \| x \| OK \| x \| x \| x \| x \| x \| x \| OK \|
185	191		\| Motorola Milestone \| 2.1 \| x \| OK \| x \| x \| x \| x \| x \| OK \| ? \|
186	192		\| Milestone 2 \| 2.2 \| x \| OK \| x \| x \| x \| x \| x \| sound-only \| OK \|
187	193
188	194		## Android file system
189	195
190	196		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\>
191	197
192	198		The native libraries of the application are placed in /data/data/\<package\>/lib
193	199
194	200		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\>
195	201
196	202		## Creating a new Java Android application
197	203
198	204		This info can be useful for helping implement LCL-CustomDrawn-Android
199	205
200	206		Generic instructions here: <http://developer.android.com/guide/developing/other-ide.html>
201	207
202	208		### Showing/hiding the virtual keyboard
203	209
204	210		See here: <http://android-codes-examples.blogspot.com/2011/11/show-or-hide-soft-keyboard-on-opening.html>
205	211
206	212		To show it:
207	213
208	214		``` java
209	215		InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
210	216		imm.toggleSoftInput(InputMethodManager.SHOW_FORCED,0);
211	217		```
212	218
213	219		and for hiding the keyboard:
214	220
215	221		``` java
216	222		InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
217	223		imm.hideSoftInputFromWindow(singleedittext.getWindowToken(),0);
218	224		```
219	225
220	226		## Android JNI
221	227
222	228		Using JNI (Java Native Interface) you can call most Android SDK APIs and also other Java libraries.
223	229
224	230		### Table of Java types and Pascal JNI types
225	231
226	232		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.
227	233
228	234		\| Java type \| VM signature \| Type in jni.pas \| Pascal equivalent \| Description \|
229	235		\|----\|----\|----\|----\|----\|
230	236		\| boolean \| Z \| jboolean \| Boolean \| \|
231	237		\| byte \| B \| jbyte \| Byte \| \|
232	238		\| char \| C \| jchar \| Word \| \|
233	239		\| short \| S \| jshort \| Shortint \| \|
234	240		\| int \| I \| jint \| Integer \| \|
235	241		\| long \| J \| jlong \| Int64 \| \|
236	242		\| float \| F \| jfloat \| Single \| \|
237	243		\| double \| D \| jdouble \| Double \| \|
238	244		\| a class, ie: String or InputStream \| L\<full class name\> ie: Ljava/lang/String; \| jobject \| N/A \| \|
239	245		\| Array, ie: int\[\] \| \[\<type-name\> ie: \[I \| N/A \| \| \|
240	246		\| A method type \| (arg-types)ref-type \| JMethodID \| N/A \| \|
241	247		\| void \| V \| N/A \| procedure \| \|
242	248
243	249		### Example 1: Creating a Java object and calling a Java method
244	250
245	251		Let's say that you want to make Pascal JNI code equivalent to the following Java code:
246	252
247	253		``` java
248	254		HttpGet javaRequest = new HttpGet();
249	255		URI myURI = new URI("http://magnifier.sourceforge.net/");
250	256		javaRequest.setURI(myURI);
251	257		```
252	258
253	259		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:
254	260
255	261		``` pascal
256	262		uses jni, customdrawnint;
257	263
258	264		var
259	265		javaClass_HttpGet, javaClass_URI: jclass;
260	266		javaMethod_HttpGet_new, javaMethod_HttpGet_setURI,
261	267		javaMethod_URI_new: jmethodid;
262	268		javaRequest, javaURI: jobject;
263	269		javaString: jstring;
264	270		lParams: array[0..2] of JValue;
265	271		lNativeString: PChar;
266	272		begin
267	273		DebugLn(':>LoadHTMLPageViaJNI');
268	274		// First call FindClass for all required classes
269	275		javaClass_HttpGet := javaEnvRef^^.FindClass(javaEnvRef,
270	276		'org/apache/http/client/methods/HttpGet');
271	277		javaClass_URI := javaEnvRef^^.FindClass(javaEnvRef,
272	278		'java/net/URI');
273	279
274	280		// Now all Method IDs
275	281		DebugLn(':LoadHTMLPageViaJNI 1');
276	282		javaMethod_HttpGet_new := javaEnvRef^^.GetMethodID(javaEnvRef, javaClass_HttpGet, '<init>', '()V');
277	283		javaMethod_HttpGet_setURI := javaEnvRef^^.GetMethodID(javaEnvRef, javaClass_HttpGet, 'setURI', '(Ljava/net/URI;)V');
278	284		javaMethod_URI_new := javaEnvRef^^.GetMethodID(javaEnvRef, javaClass_URI, '<init>', '(Ljava/lang/String;)V');
279	285
280	286		// Create a new instance for the HTTP request object
281	287		// HttpGet javaRequest = new HttpGet();
282	288		javaRequest := javaEnvRef^^.NewObject(javaEnvRef,
283	289		javaClass_HttpGet,
284	290		javaMethod_HttpGet_new);
285	291
286	292		DebugLn(':LoadHTMLPageViaJNI 4 javaRequest='+IntToHex(PtrInt(javaRequest), 8));
287	293		// Add a URI for the request object
288	294		// URI javaURI = new URI("http://magnifier.sourceforge.net/");
289	295		lParams[0].l := javaEnvRef^^.NewStringUTF(javaEnvRef, 'http://magnifier.sourceforge.net');
290	296		javaURI := javaEnvRef^^.NewObjectA(javaEnvRef,
291	297		javaClass_URI, javaMethod_URI_new, @lParams[0]);
292	298		javaEnvRef^^.DeleteLocalRef(javaEnvRef, lParams[0].l);
293	299		// javaRequest.setURI(javaURI);
294	300		lParams[0].l := javaURI;
295	301		javaEnvRef^^.CallVoidMethodA(javaEnvRef, javaRequest,
296	302		javaMethod_HttpGet_setURI, @lParams[0]);
297	303		```
298	304
299	305		### Example 2: Calling a static method
300	306
301	307		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>
302	308
303	309		``` java
304	310		public static native int BASS_StreamCreateFile(String file, long offset, long length, int flags);
305	311		```
306	312
307	313		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:
308	314
309	315		``` pascal
310	316		uses jni, customdrawnint;
311	317
312	318		var
313	319		javaClass_Bass: jclass;
314	320		javaMethod_Bass_BASS_StreamCreateFile: jmethodid;
315	321		javaString: jstring;
316	322		lParams: array[0..3] of JValue;
317	323		lRetInt: jint;
318	324		begin
319	325		// First call FindClass for all required classes
320	326		javaClass_Bass := javaEnvRef^^.FindClass(javaEnvRef, 'org/jouvieje/bass/Bass');
321	327
322	328		// Now all Method IDs
323	329		javaMethod_Bass_BASS_StreamCreateFile := javaEnvRef^^.GetStaticMethodID(javaEnvRef, javaClass_Bass, 'BASS_StreamCreateFile', '(Ljava/lang/String;JJI)I');
324	330
325	331		// Make the call
326	332		lParams[0].l := javaEnvRef^^.NewStringUTF(javaEnvRef, '/path/to/file');
327	333		lParams[1].j := 0; // offset
328	334		lParams[2].j := 200; // length
329	335		lParams[3].i := 0; // flags
330	336		lRetInt := javaEnvRef^^.CallStaticIntMethodA(javaEnvRef, javaClass_Bass, javaMethod_Bass_BASS_StreamCreateFile, @lParams[0]);
331	337		javaEnvRef^^.DeleteLocalRef(javaEnvRef, lParams[0].l);
332	338		```
333	339
334	340		## References
335	341
336	342		- <http://developer.android.com/guide/developing/other-ide.html>
337	343		- [Tutorial "Lazarus and Android"](https://dl.dropboxusercontent.com/u/3753548/Lazarus%20and%20Android.pdf) (PDF file)
338	344
339	345		---
340	346		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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