Android getActivity() 找不到符号符号：方法 getActivity()
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时间：2020-08-20 10:35:08 来源:igfitidea点击:
getActivity() cannot find symbol symbol : method getActivity()
提问by user1668707
I need help with this file for my mms app. getActivity()causes an error in the build.
我的 mms 应用程序需要有关此文件的帮助。getActivity()导致构建错误。
Error:cannot find symbol: method getActivity()
错误：cannot find symbol: method getActivity()
I have tried numerous things to make this work so far, like extends PreferenceFragment- then getActivity()is fine, but this solution breaks tons of other stuff.
到目前为止，我已经尝试了很多方法来完成这项工作，比如extends PreferenceFragment- 那么getActivity()很好，但是这个解决方案打破了很多其他的东西。
Does anyone know why I'm getting this error?
有谁知道我为什么会收到这个错误？
My code:
我的代码：
package com.android.mms.themes;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URISyntaxException;
import android.app.Activity;
import android.app.ActionBar;
import android.app.Fragment;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.res.Configuration;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.Drawable;
import android.graphics.Rect;
import android.net.Uri;
import android.os.Bundle;
import android.os.SystemProperties;
import android.preference.CheckBoxPreference;
import android.preference.EditTextPreference;
import android.preference.ListPreference;
import android.preference.Preference;
import android.preference.PreferenceActivity;
import android.preference.PreferenceFragment;
import android.preference.PreferenceGroup;
import android.preference.PreferenceManager;
import android.preference.Preference.OnPreferenceChangeListener;
import android.preference.PreferenceScreen;
import android.provider.MediaStore;
import android.text.Spannable;
import android.util.Log;
import android.view.Display;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.Window;
import com.android.mms.R;
import com.android.mms.ui.ColorPickerPreference;
public class ThemesMessageList extends PreferenceActivity implements
Preference.OnPreferenceChangeListener {
// Menu entries
private static final int THEMES_RESTORE_DEFAULTS = 1;
// Layout Style
public static final String PREF_TEXT_CONV_LAYOUT = "pref_text_conv_layout";
// Msg background
public static final String PREF_MESSAGE_BG = "pref_message_bg";
private static final String CUSTOM_IMAGE = "message_list_image.jpg";
private static final int REQUEST_PICK_WALLPAPER = 201;
private static final int SELECT_WALLPAPER = 5;
// Bubble types
public static final String PREF_BUBBLE_TYPE = "pref_bubble_type";
public static final String PREF_BUBBLE_FILL_PARENT = "pref_bubble_fill_parent";
// Checkbox preferences
public static final String PREF_USE_CONTACT = "pref_use_contact";
public static final String PREF_SHOW_AVATAR = "pref_show_avatar";
// Colorpicker preferences send
public static final String PREF_SENT_TEXTCOLOR = "pref_sent_textcolor";
public static final String PREF_SENT_CONTACT_COLOR = "pref_sent_contact_color";
public static final String PREF_SENT_DATE_COLOR = "pref_sent_date_color";
public static final String PREF_SENT_TEXT_BG = "pref_sent_text_bg";
public static final String PREF_SENT_SMILEY = "pref_sent_smiley";
// Colorpicker preferences received
public static final String PREF_RECV_TEXTCOLOR = "pref_recv_textcolor";
public static final String PREF_RECV_CONTACT_COLOR = "pref_recv_contact_color";
public static final String PREF_RECV_DATE_COLOR = "pref_recv_date_color";
public static final String PREF_RECV_TEXT_BG = "pref_recv_text_bg";
public static final String PREF_RECV_SMILEY = "pref_recv_smiley";
// message background
ColorPickerPreference mMessageBackground;
// send
ColorPickerPreference mSentTextColor;
ColorPickerPreference mSentDateColor;
ColorPickerPreference mSentContactColor;
ColorPickerPreference mSentTextBgColor;
ColorPickerPreference mSentSmiley;
// received
ColorPickerPreference mRecvTextColor;
ColorPickerPreference mRecvContactColor;
ColorPickerPreference mRecvDateColor;
ColorPickerPreference mRecvTextBgColor;
ColorPickerPreference mRecvSmiley;
private CheckBoxPreference mUseContact;
private CheckBoxPreference mShowAvatar;
private CheckBoxPreference mBubbleFillParent;
private ListPreference mTextLayout;
private ListPreference mBubbleType;
private Preference mCustomImage;
private SharedPreferences sp;
protected Context mContext;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mContext = getActivity();
loadThemePrefs();
ActionBar actionBar = getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
}
public void loadThemePrefs() {
// Load the preferences from an XML resource
addPreferencesFromResource(R.xml.preferences_themes_msglist);
PreferenceScreen prefSet = getPreferenceScreen();
sp = PreferenceManager.getDefaultSharedPreferences(this);
mUseContact = (CheckBoxPreference) prefSet.findPreference(PREF_USE_CONTACT);
mShowAvatar = (CheckBoxPreference) prefSet.findPreference(PREF_SHOW_AVATAR);
mBubbleFillParent = (CheckBoxPreference) prefSet.findPreference(PREF_BUBBLE_FILL_PARENT);
mTextLayout = (ListPreference) findPreference(PREF_TEXT_CONV_LAYOUT);
mTextLayout.setOnPreferenceChangeListener(this);
mTextLayout.setSummary(mTextLayout.getEntry());
mBubbleType = (ListPreference) findPreference(PREF_BUBBLE_TYPE);
mBubbleType.setOnPreferenceChangeListener(this);
mBubbleType.setSummary(mBubbleType.getEntry());
mCustomImage = findPreference("pref_custom_image");
mMessageBackground = (ColorPickerPreference) findPreference(PREF_MESSAGE_BG);
mMessageBackground.setOnPreferenceChangeListener(this);
mSentTextColor = (ColorPickerPreference) findPreference(PREF_SENT_TEXTCOLOR);
mSentTextColor.setOnPreferenceChangeListener(this);
mSentContactColor = (ColorPickerPreference) findPreference(PREF_SENT_TEXTCOLOR);
mSentContactColor.setOnPreferenceChangeListener(this);
mSentDateColor = (ColorPickerPreference) findPreference(PREF_SENT_TEXTCOLOR);
mSentDateColor.setOnPreferenceChangeListener(this);
mSentTextBgColor = (ColorPickerPreference) findPreference(PREF_SENT_TEXTCOLOR);
mSentTextBgColor.setOnPreferenceChangeListener(this);
mSentSmiley = (ColorPickerPreference) findPreference(PREF_SENT_SMILEY);
mSentSmiley.setOnPreferenceChangeListener(this);
mRecvTextColor = (ColorPickerPreference) findPreference(PREF_RECV_TEXTCOLOR);
mRecvTextColor.setOnPreferenceChangeListener(this);
mRecvContactColor = (ColorPickerPreference) findPreference(PREF_RECV_TEXTCOLOR);
mRecvContactColor.setOnPreferenceChangeListener(this);
mRecvDateColor = (ColorPickerPreference) findPreference(PREF_RECV_TEXTCOLOR);
mRecvDateColor.setOnPreferenceChangeListener(this);
mRecvTextBgColor = (ColorPickerPreference) findPreference(PREF_RECV_TEXT_BG);
mRecvTextBgColor.setOnPreferenceChangeListener(this);
mRecvSmiley = (ColorPickerPreference) findPreference(PREF_RECV_SMILEY);
mRecvSmiley.setOnPreferenceChangeListener(this);
}
@Override
public boolean onPreferenceChange(Preference preference, Object newValue) {
boolean result = false;
if (preference == mMessageBackground) {
String hex = ColorPickerPreference.convertToARGB(Integer.valueOf(String
.valueOf(newValue)));
mMessageBackground.setSummary(hex);
} else if (preference == mSentTextColor) {
String hex = ColorPickerPreference.convertToARGB(Integer.valueOf(String
.valueOf(newValue)));
mSentTextColor.setSummary(hex);
} else if (preference == mSentContactColor) {
String hex = ColorPickerPreference.convertToARGB(Integer.valueOf(String
.valueOf(newValue)));
mSentContactColor.setSummary(hex);
} else if (preference == mSentDateColor) {
String hex = ColorPickerPreference.convertToARGB(Integer.valueOf(String
.valueOf(newValue)));
mSentDateColor.setSummary(hex);
} else if (preference == mSentTextBgColor) {
String hex = ColorPickerPreference.convertToARGB(Integer.valueOf(String
.valueOf(newValue)));
mSentTextBgColor.setSummary(hex);
} else if (preference == mSentSmiley) {
String hex = ColorPickerPreference.convertToARGB(Integer.valueOf(String
.valueOf(newValue)));
mSentSmiley.setSummary(hex);
} else if (preference == mRecvTextColor) {
String hex = ColorPickerPreference.convertToARGB(Integer.valueOf(String
.valueOf(newValue)));
mRecvTextColor.setSummary(hex);
} else if (preference == mRecvContactColor) {
String hex = ColorPickerPreference.convertToARGB(Integer.valueOf(String
.valueOf(newValue)));
mRecvContactColor.setSummary(hex);
} else if (preference == mRecvDateColor) {
String hex = ColorPickerPreference.convertToARGB(Integer.valueOf(String
.valueOf(newValue)));
mRecvDateColor.setSummary(hex);
} else if (preference == mRecvTextBgColor) {
String hex = ColorPickerPreference.convertToARGB(Integer.valueOf(String
.valueOf(newValue)));
mRecvTextBgColor.setSummary(hex);
} else if (preference == mRecvSmiley) {
String hex = ColorPickerPreference.convertToARGB(Integer.valueOf(String
.valueOf(newValue)));
mRecvSmiley.setSummary(hex);
} else if (preference == mTextLayout) {
int index = mTextLayout.findIndexOfValue((String) newValue);
mTextLayout.setSummary(mTextLayout.getEntries()[index]);
return true;
} else if (preference == mBubbleType) {
int index = mBubbleType.findIndexOfValue((String) newValue);
mBubbleType.setSummary(mBubbleType.getEntries()[index]);
return true;
}
return result;
}
@Override
public boolean onPreferenceTreeClick(PreferenceScreen preferenceScreen, Preference preference) {
boolean value;
if (preference == mCustomImage) {
Display display = getActivity().getWindowManager().getDefaultDisplay();
int width = display.getWidth();
int height = display.getHeight();
Rect rect = new Rect();
Window window = getActivity().getWindow();
window.getDecorView().getWindowVisibleDisplayFrame(rect);
int statusBarHeight = rect.top;
int contentViewTop = window.findViewById(Window.ID_ANDROID_CONTENT).getTop();
int titleBarHeight = contentViewTop - statusBarHeight;
Intent intent = new Intent(Intent.ACTION_GET_CONTENT, null);
intent.setType("image/*");
intent.putExtra("crop", "true");
boolean isPortrait = getResources()
.getConfiguration().orientation
== Configuration.ORIENTATION_PORTRAIT;
intent.putExtra("aspectX", isPortrait ? width : height - titleBarHeight);
intent.putExtra("aspectY", isPortrait ? height - titleBarHeight : width);
intent.putExtra("outputX", width);
intent.putExtra("outputY", height);
intent.putExtra("scale", true);
intent.putExtra("scaleUpIfNeeded", true);
intent.putExtra(MediaStore.EXTRA_OUTPUT, getCustomImageExternalUri());
intent.putExtra("outputFormat", Bitmap.CompressFormat.PNG.toString());
startActivityForResult(intent, REQUEST_PICK_WALLPAPER);
return true;
} else if (preference == mUseContact) {
value = mUseContact.isChecked();
} else if (preference == mShowAvatar) {
value = mShowAvatar.isChecked();
} else if (preference == mBubbleFillParent) {
value = mShowAvatar.isChecked();
}
return super.onPreferenceTreeClick(preferenceScreen, preference);
}
private void restoreThemeMessageListDefaultPreferences() {
PreferenceManager.getDefaultSharedPreferences(this).edit().clear().apply();
setPreferenceScreen(null);
loadThemePrefs();
}
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
menu.clear();
menu.add(R.menu.themes_message_list);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case THEMES_RESTORE_DEFAULTS:
restoreThemeMessageListDefaultPreferences();
return true;
case R.id.custom_image_delete:
deleteCustomImage();
return true;
case android.R.id.home:
// The user clicked on the Messaging icon in the action bar. Take them back from
// wherever they came from
finish();
return true;
}
return false;
}
private void deleteCustomImage() {
mContext.deleteFile(CUSTOM_IMAGE);
}
private Uri getCustomImageExternalUri() {
File dir = mContext.getExternalCacheDir();
File wallpaper = new File(dir, CUSTOM_IMAGE);
return Uri.fromFile(wallpaper);
}
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode == Activity.RESULT_OK) {
if (requestCode == REQUEST_PICK_WALLPAPER) {
FileOutputStream wallpaperStream = null;
try {
wallpaperStream = mContext.openFileOutput(CUSTOM_IMAGE,
Context.MODE_WORLD_READABLE);
} catch (FileNotFoundException e) {
return; // NOOOOO
}
Uri selectedImageUri = getCustomImageExternalUri();
Bitmap bitmap = BitmapFactory.decodeFile(selectedImageUri.getPath());
bitmap.compress(Bitmap.CompressFormat.PNG, 100, wallpaperStream);
}
}
}
public void copy(File src, File dst) throws IOException {
InputStream in = new FileInputStream(src);
FileOutputStream out = new FileOutputStream(dst);
// Transfer bytes from in to out
byte[] buf = new byte[1024];
int len;
while ((len = in.read(buf)) > 0) {
out.write(buf, 0, len);
}
in.close();
out.close();
}
}
回答by Marcin Orlowski
getActivity()does not exists in Activityclass, so to get Contextof your Activity, just use thisinstead:
getActivity()Activity类中不存在，因此要获取Context您的 Activity，只需使用this：
mContext = this;
as Activity is a child (subclass) of Context
因为 Activity 是 Context 的子类（子类）
https://developer.android.com/reference/android/app/Activity
https://developer.android.com/reference/android/app/Activity
回答by Michael Celey
PreferenceActivitydoesn't have a getActivitymethod because it IS an Activity. Just assign your context like so: mContext = this;
PreferenceActivity没有getActivity方法，因为它是Activity. 只需像这样分配您的上下文：mContext = this;
getActivity()is a method of the Fragmentclass.
getActivity()是Fragment类的方法。
Also, unless you're trying to reference mContextoutside of this class, you can ditch it all together and just use thisinstead.
此外，除非您尝试在mContext该类之外进行引用，否则您可以将其全部丢弃并this改为使用。
回答by Rajeev Kashyap
Try this :-
尝试这个 ：-
Right click on project >properties > java build path > click on Libraries Tab >Click on add Library Button > select Jre System Library >Next > Finish >ok
右键单击项目>属性> java构建路径>单击库选项卡>单击添加库按钮>选择Jre系统库>下一步>完成>确定
