为此,我将一个首选项放入设置xml中,如下所示(我的首选项是flash_设置.xml);
<Preference
android:key="image_custom"
android:title="Choose Background"
android:summary="Select a Custom Image"
/>
我创建了一个自定义类来获取OnPreferenceClick监听器,并观察用户是否按原样单击首选项(这是一个调用)mySettings.java文件)(请注意getRealPathFromURI例程不是我的,而是在这里的其他地方找到的);
您的类应该从扩展PreferenceActivity和实现Sharedpreference更改侦听器开始
public class flashSettings extends PreferenceActivityimplements SharedPreferences.OnSharedPreferenceChangeListener {
链接到首选项名称并注册侦听器
@Override
protected void onCreate(Bundle icicle) {
super.onCreate(icicle);
getPreferenceManager().setSharedPreferencesName(
fingerflashpro.SHARED_PREFS_NAME);
addPreferencesFromResource(R.xml.flash_settings); getPreferenceManager().getSharedPreferences().registerOnSharedPreferenceChangeListener(
this);
接下来,我们将在首选项侦听器上设置“image\u custom”。单击它时,我们将启动一个新的意图来显示照片选择器。我们从StartActivityForResult开始,这样就可以从intent中获取图像的URI。
getPreferenceManager().findPreference("image_custom").setOnPreferenceClickListener(new OnPreferenceClickListener()
{
@Override
public boolean onPreferenceClick(Preference preference)
{
Display display = getWindowManager().getDefaultDisplay();
int width = display.getWidth();
int height = display.getHeight();
Toast.makeText(getBaseContext(), "Select Image - " + (width) + " x " + height , Toast.LENGTH_LONG).show();
Intent photoPickerIntent = new Intent(Intent.ACTION_PICK);
photoPickerIntent.setType("image/*");
startActivityForResult(photoPickerIntent, 1);
return true;
}
});}
接下来,我们等待活动返回结果,并将URI解析为实际路径。
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 1) {
if (resultCode == Activity.RESULT_OK) {
Uri selectedImage = data.getData();
String RealPath;
SharedPreferences customSharedPreference = getSharedPreferences(fingerflashpro.SHARED_PREFS_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = customSharedPreference.edit ();
RealPath = getRealPathFromURI (selectedImage);
editor.putString("image_custom", RealPath);
editor.commit();
}}
this thread
)我只是为了完整才写的。不过,它确实工作得很好。
public String getRealPathFromURI(Uri contentUri) {
String [] proj={MediaColumns.DATA};
Cursor cursor = managedQuery( contentUri,
proj, // Which columns to return
null, // WHERE clause; which rows to return (all rows)
null, // WHERE clause selection arguments (none)
null); // Order-by clause (ascending by name)
int column_index = cursor.getColumnIndexOrThrow(MediaColumns.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);}
@Override
protected void onResume() {
super.onResume();
}
@Override
protected void onDestroy() {
getPreferenceManager().getSharedPreferences().
unregisterOnSharedPreferenceChangeListener(this);
super.onDestroy();
}
@Override
public void onSharedPreferenceChanged(SharedPreferences sharedPreferences,
String key) {
}}
然后在主墙纸服务活动中,您可以从共享的首选项中提取图像的路径。
@Override
public void onSharedPreferenceChanged(SharedPreferences prefs,
String key) {
imageBg = prefs.getString("image_custom", "Bad Image");
getBackground();}
这里有一个相当粗糙的例程来加载图像。我试图在一些错误陷阱只是为了防止文件被删除,重命名或SD卡挂载(因此你失去你的形象)。我还尝试对设备的方向进行一些粗略的检查。我相信你能做得更好。
当手机的方向改变时,我也会调用这个例程,以便每次调整背景的大小。
void getBackground() {
if (this.cvwidth == 0 || this.cvheight == 0 || this.visibleWidth == 0) {
this.cvwidth = 480;
this.cvheight = 854;
this.visibleWidth = 480;}
if(new File(imageBg).exists()) {
int SampleSize = 1;
do {
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
bg = BitmapFactory.decodeFile(imageBg, options);
SampleSize = (int) (Math.ceil(options.outWidth/(this.visibleWidth * 2))*2);
options.inJustDecodeBounds = false;
try {options.inSampleSize = SampleSize;
bg = BitmapFactory.decodeFile(imageBg, options);}
catch (OutOfMemoryError e) {
SampleSize = SampleSize * 2;
}
} while (bg == null);
bg = Bitmap.createScaledBitmap(bg, this.cvwidth/2, this.cvheight, true);}
else {bg = BitmapFactory.decodeResource(getResources(), R.drawable.bg);
bg = Bitmap.createScaledBitmap(bg, this.cvwidth/2, this.cvheight, true);}
LoadText = "";
}
我希望这有帮助。我花了我一个绝对的年龄来想出这一切,我知道还有一些领域,我可以完善,但至少它应该让你去。
如果有人对改进这段代码有什么建议的话,我洗耳恭听。
