android-为什么startActivityForResult不返回任何东西?
作者:互联网
我在PreferenceActivity中有一个“选择图像”:
Intent i = new Intent(Intent.ACTION_PICK,
android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(i, IMAGE_SELECT);
但是,当我从图库中选择图像时,它不会返回任何东西到我的PreferenceActivity的onActivityResult中:
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
Toast.makeText(getApplicationContext(), "THIS TOAST IS NOT SHOWING",
Toast.LENGTH_LONG).show();
}
我还需要做什么?在清单中添加一些内容?不可能吗
这是我的“整个”课程(省略了不相关的代码):
package com.xuso.myapp;
import yuku.ambilwarna.AmbilWarnaDialog;
import yuku.ambilwarna.AmbilWarnaDialog.OnAmbilWarnaListener;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.preference.CheckBoxPreference;
import android.preference.ListPreference;
import android.preference.Preference;
import android.preference.Preference.OnPreferenceChangeListener;
import android.preference.Preference.OnPreferenceClickListener;
import android.preference.PreferenceActivity;
import android.provider.MediaStore;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
import android.widget.TextView;
import android.widget.Toast;
public class Settings extends PreferenceActivity {
protected static final int NEED_RESTART = 2;
protected static final int IMAGE_SELECT = 3;
private int bg_color; //There are a lot more
private Context context = this;
private int result = RESULT_CANCELED;
private SharedPreferences sp;
private SharedPreferences.Editor editor;
Preference pref_bg_color; //There are a lot more
public void getPrefs(){
sp = getSharedPreferences("myapp_prefs", Activity.MODE_PRIVATE);
editor = sp.edit();
bg_color = sp.getInt("pref_bg_color", 0xff000000);
//... and the rest of the GETs.
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.settings);
getPrefs();
//A lot of declarations of listeners when Preferences pressed
//...
//...
pref_bg_image.setOnPreferenceClickListener(new OnPreferenceClickListener() {
@Override
public boolean onPreferenceClick(Preference preference) {
Intent i = new Intent(Intent.ACTION_PICK,
android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(i, IMAGE_SELECT);
return false;
}
});
//...
//...
//More and more declarations of Preferences.
}
//This is for returning results with preferences changes to the Main activity
private void getBackAndCommit()
{
Intent intent= getIntent();
setResult(result, intent);
finish();
overridePendingTransition(0, 0);
}
//Commit changes on back pressed
public void onBackPressed ()
{
getBackAndCommit();
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch(requestCode) {
case IMAGE_SELECT:
if(resultCode == RESULT_OK){
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]);
String filePath = cursor.getString(columnIndex);
cursor.close();
Bitmap yourSelectedImage = BitmapFactory.decodeFile(filePath);
}
}
}
}
这是我的清单:
<application android:icon="@drawable/myapp_icon" android:label="@string/app_name"
>
<activity android:name=".Main"
android:label="@string/app_name"
android:theme="@android:style/Theme.NoTitleBar"
>
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".Settings"
android:label="@string/app_name"
>
</activity>
</application>
解决方法:
必须工作,增加全班:
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
public class StackOverflowAppActivity extends Activity {
private final int PICK_IMAGE = 0;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Intent i = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(i, PICK_IMAGE);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
switch (requestCode) {
case PICK_IMAGE:
if (resultCode == RESULT_OK) {
// do your thing
}
}
}
}
标签:onactivityresult,android-activity,android 来源: https://codeday.me/bug/20191102/1991734.html