targetSdkVersion 23 returns 0 长度数组通过 accountManager.getAccounts()
targetSdkVersion 23 returns 0 length array via accountManager.getAccounts()
我在我的真实 Nexus 5 设备 Android 6.0.1
中观察到以下奇怪的结果
我 运行 在我的应用程序启动期间使用了以下简单代码。
Pattern emailPattern = Patterns.EMAIL_ADDRESS; // API level 8+
AccountManager accountManager = AccountManager.get(this);
Account[] accounts = accountManager.getAccounts();
如果我将 targetSdkVersion
设置为 22、21、19,上面的代码工作正常。它 returns 非空数组。
但是,当我更改 targetSdkVersion
并使用
进行测试时
defaultConfig {
applicationId "org.yccheok.myapplication"
minSdkVersion 19
targetSdkVersion 23
versionCode 1
versionName "1.0"
}
以上代码returns0长度数组!
知道为什么在针对 targetSdkVersion=23
.
编译时会出现问题
请注意,在产生问题期间,每当您通过 Android Studio 更改 targetSdkVersion
和 运行 时,您需要 清除您的应用程序数据,清除您的应用缓存并为所有用户手动卸载。
以下是在 Nexus 5 设备 Android 6.0.1
中重现问题的步骤
- 通过文件 -> 新建 -> 新建项目在 Android Studio 中创建项目...
- 选择"Blank Activity"
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="org.yccheok.myapplication">
<uses-permission android:name="android.permission.GET_ACCOUNTS"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity
android:name=".MainActivity"
android:label="@string/app_name"
android:theme="@style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
build.gradle
apply plugin: 'com.android.application'
android {
compileSdkVersion 23
buildToolsVersion "23.0.1"
defaultConfig {
applicationId "org.yccheok.myapplication"
minSdkVersion 19
targetSdkVersion 23
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.1.1'
compile 'com.android.support:design:23.1.1'
}
MainActivity.java
import android.accounts.Account;
import android.accounts.AccountManager;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Patterns;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import java.util.regex.Pattern;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
int targetSdkVersion = 0;
try {
PackageInfo packageInfo = getPackageManager().getPackageInfo(getPackageName(), 0);
targetSdkVersion = packageInfo.applicationInfo.targetSdkVersion;
}
catch (PackageManager.NameNotFoundException e) {
android.util.Log.i("CHEOK", e.getMessage());
}
Pattern emailPattern = Patterns.EMAIL_ADDRESS; // API level 8+
AccountManager accountManager = AccountManager.get(this);
Account[] accounts = accountManager.getAccounts();
android.util.Log.i("CHEOK", targetSdkVersion + " : numnber of accoutn by ??? = " + accounts.length);
for (Account account : accounts) {
if (emailPattern.matcher(account.name).matches()) {
String possibleEmail = account.name;
android.util.Log.i("CHEOK", "possibleEmail = " + possibleEmail);
}
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, 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();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
知道为什么 targetSdkVersion 23 returns 0 长度数组通过 accountManager.getAccounts()
GET_ACCOUNTS 是 dangerous permission and when using target sdk 23 needs to be managed with runtime permissions 否则将不起作用。
您实际上需要在运行时从用户那里 request permission。
示例:
ActivityCompat.requestPermissions(this, new String[]
{Manifest.permission.GET_ACCOUNTS}, 1);
int permissionCheck = ContextCompat.checkSelfPermission(thisActivity,
Manifest.permission.GET_ACCOUNTS);
我在 中对此进行了详细介绍。
Dangerous permissions cover areas where the app wants data or resources that involve the user's private information, or could potentially affect the user's stored data or the operation of other apps. For example, the ability to read the user's contacts is a dangerous permission. If an app declares that it needs a dangerous permission, the user has to explicitly grant the permission to the app.
我在我的真实 Nexus 5 设备 Android 6.0.1
中观察到以下奇怪的结果我 运行 在我的应用程序启动期间使用了以下简单代码。
Pattern emailPattern = Patterns.EMAIL_ADDRESS; // API level 8+
AccountManager accountManager = AccountManager.get(this);
Account[] accounts = accountManager.getAccounts();
如果我将 targetSdkVersion
设置为 22、21、19,上面的代码工作正常。它 returns 非空数组。
但是,当我更改 targetSdkVersion
并使用
defaultConfig {
applicationId "org.yccheok.myapplication"
minSdkVersion 19
targetSdkVersion 23
versionCode 1
versionName "1.0"
}
以上代码returns0长度数组!
知道为什么在针对 targetSdkVersion=23
.
请注意,在产生问题期间,每当您通过 Android Studio 更改 targetSdkVersion
和 运行 时,您需要 清除您的应用程序数据,清除您的应用缓存并为所有用户手动卸载。
以下是在 Nexus 5 设备 Android 6.0.1
中重现问题的步骤- 通过文件 -> 新建 -> 新建项目在 Android Studio 中创建项目...
- 选择"Blank Activity"
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="org.yccheok.myapplication">
<uses-permission android:name="android.permission.GET_ACCOUNTS"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity
android:name=".MainActivity"
android:label="@string/app_name"
android:theme="@style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
build.gradle
apply plugin: 'com.android.application'
android {
compileSdkVersion 23
buildToolsVersion "23.0.1"
defaultConfig {
applicationId "org.yccheok.myapplication"
minSdkVersion 19
targetSdkVersion 23
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.1.1'
compile 'com.android.support:design:23.1.1'
}
MainActivity.java
import android.accounts.Account;
import android.accounts.AccountManager;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Patterns;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import java.util.regex.Pattern;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
int targetSdkVersion = 0;
try {
PackageInfo packageInfo = getPackageManager().getPackageInfo(getPackageName(), 0);
targetSdkVersion = packageInfo.applicationInfo.targetSdkVersion;
}
catch (PackageManager.NameNotFoundException e) {
android.util.Log.i("CHEOK", e.getMessage());
}
Pattern emailPattern = Patterns.EMAIL_ADDRESS; // API level 8+
AccountManager accountManager = AccountManager.get(this);
Account[] accounts = accountManager.getAccounts();
android.util.Log.i("CHEOK", targetSdkVersion + " : numnber of accoutn by ??? = " + accounts.length);
for (Account account : accounts) {
if (emailPattern.matcher(account.name).matches()) {
String possibleEmail = account.name;
android.util.Log.i("CHEOK", "possibleEmail = " + possibleEmail);
}
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, 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();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
知道为什么 targetSdkVersion 23 returns 0 长度数组通过 accountManager.getAccounts()
GET_ACCOUNTS 是 dangerous permission and when using target sdk 23 needs to be managed with runtime permissions 否则将不起作用。
您实际上需要在运行时从用户那里 request permission。 示例:
ActivityCompat.requestPermissions(this, new String[]
{Manifest.permission.GET_ACCOUNTS}, 1);
int permissionCheck = ContextCompat.checkSelfPermission(thisActivity,
Manifest.permission.GET_ACCOUNTS);
我在
Dangerous permissions cover areas where the app wants data or resources that involve the user's private information, or could potentially affect the user's stored data or the operation of other apps. For example, the ability to read the user's contacts is a dangerous permission. If an app declares that it needs a dangerous permission, the user has to explicitly grant the permission to the app.