我想使用sharedpreferences当用户选择一个特定的自定义图像,他们想要在他们的存储部分网格图像。即使在关闭应用程序并重新打开之后,我也希望他们选择显示的图像。我遇到的问题是共享首选似乎不起作用。没有任何东西显示为他们关闭应用后选择的网格项的背景图像,甚至只是按下后退按钮。sharedpreferences没有加载或保存
我必须自己创建一个sharedpreferences文件吗?我无法弄清楚如何使用androidstudio来创建一个。
这里是我的类代码(很抱歉,如果它的长和凌乱......我是新来的编码和仍在测试的东西):
public class editCreations extends Activity {
public int mPosition = 0;
protected static Sounds sound = new Sounds();
private static int RESULT_LOAD_IMAGE = 1;
private MediaRecorder mRecorder;
private MediaPlayer mPlayer;
private String mOutputFile = Environment.getExternalStorageDirectory().getAbsolutePath();
private Drawable mImageFileName;
private Button recordBtn;
private Button stopBtn;
private Button playBtn;
private Button stopPlayBtn;
private ImageButton imgBtn;
private Drawable bg;
private String mPicturePath;
private ImageAdapter img = new ImageAdapter(this);
View.OnClickListener playListener = new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(editCreations.this, "test", Toast.LENGTH_SHORT);
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_create);
mRecorder = new MediaRecorder();
mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mRecorder.setAudioEncoder(MediaRecorder.OutputFormat.AMR_NB);
mRecorder.setOutputFile(mOutputFile);
recordBtn = (Button)findViewById(R.id.create_record_button);
recordBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
start(view);
}
});
stopBtn = (Button)findViewById(R.id.create_stop_record_button);
stopBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
stop(view);
}
});
playBtn = (Button)findViewById(R.id.create_play_button);
playBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
play(view);
}
});
stopPlayBtn = (Button)findViewById(R.id.create_stop_button);
stopPlayBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
stopPlay(view);
}
});
imgBtn = (ImageButton)findViewById(R.id.imageButton);
Intent extra = getIntent();
Bundle extras = extra.getExtras();
// gave mPosition a default int to debug and find problem -> found it
mPosition = extras.getInt("position");
getSelectedFile(mPosition);
imgBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent i = new Intent(
Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(i, RESULT_LOAD_IMAGE);
}
});
}
public void start (View view) {
try {
mRecorder.prepare();
mRecorder.start();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
recordBtn.setEnabled(false);
stopBtn.setEnabled(true);
Toast.makeText(editCreations.this, mPosition + "!", Toast.LENGTH_SHORT).show();
}
public void stop(View view){
try {
mRecorder.stop();
mRecorder.release();
mRecorder = null;
stopBtn.setEnabled(false);
recordBtn.setEnabled(true);
Toast.makeText(getApplicationContext(), "Stop recording...",
Toast.LENGTH_SHORT).show();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (RuntimeException e) {
e.printStackTrace();
}
}
public void play(View view) {
try{
mPlayer = new MediaPlayer();
mPlayer.setDataSource(mOutputFile);
mPlayer.prepare();
mPlayer.start();
playBtn.setEnabled(false);
stopPlayBtn.setEnabled(true);
Toast.makeText(getApplicationContext(), "Start play the recording...",
Toast.LENGTH_SHORT).show();
} catch (Exception e) {
e.printStackTrace();
}
}
public void stopPlay(View view) {
try {
if (mPlayer != null) {
mPlayer.stop();
mPlayer.release();
mPlayer = null;
playBtn.setEnabled(true);
stopPlayBtn.setEnabled(false);
Toast.makeText(getApplicationContext(), "Stop playing the recording...",
Toast.LENGTH_SHORT).show();
}
} catch (Exception e){
e.printStackTrace();
}
}
public void getSoundPosition(int position) {
mOutputFile = mOutputFile + "/Lollatone_clip_" + mPosition + ".3gpp";
// use to get proper image and sound files and edit output file to proper name
}
public void getSelectedFile(int position) {
switch (mPosition) {
case 0:
imgBtn.setBackgroundResource(R.drawable.sample_0);
imgBtn.refreshDrawableState();
break;
case 1:
imgBtn.setImageBitmap(BitmapFactory.decodeFile(mPicturePath));
imgBtn.refreshDrawableState();
break;
case 2:
imgBtn.setImageBitmap(BitmapFactory.decodeFile(mPicturePath));
imgBtn.refreshDrawableState();
break;
case 3:
imgBtn.setImageBitmap(BitmapFactory.decodeFile(mPicturePath));
imgBtn.refreshDrawableState();
break;
case 4:
imgBtn.setBackgroundResource(R.drawable.sample_4);
imgBtn.refreshDrawableState();
break;
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.edit_creations, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode,resultCode,data);
if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && null != data) {
Uri selectedImage = data.getData();
String[] filePathColumn = { MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(selectedImage,
filePathColumn, null,null,null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
mPicturePath = cursor.getString(columnIndex);
cursor.close();
imgBtn.setImageBitmap(BitmapFactory.decodeFile(mPicturePath));
imgBtn.refreshDrawableState();
// String picturePath contains the path of
// selected image
}
}
protected void onPause() {
super.onPause();
//need an editor object to make preference changes
// all objects are from android.context.Context
SharedPreferences sharedPref = getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putString("img_" + mPosition, mPicturePath);
editor.commit();
}
protected void onResume() {
super.onResume();
SharedPreferences sharedPref = getPreferences(Context.MODE_PRIVATE);
mPicturePath = sharedPref.getString("img_" + mPosition, "img_" + mPosition);
}
}
它仍然不起作用 – user3417966 2014-10-04 23:21:03
没关系。我忘了更新onResume中的图像。它现在工作,谢谢! – user3417966 2014-10-04 23:29:26