// Here, thisActivity is the current activity
if (ContextCompat.checkSelfPermission(thisActivity,
Manifest.permission.READ_CONTACTS)
!= PackageManager.PERMISSION_GRANTED) {
// Should we show an explanation?
if (ActivityCompat.shouldShowRequestPermissionRationale(thisActivity,
Manifest.permission.READ_CONTACTS)) {
// Show an expanation to the user *asynchronously* -- don't block
// this thread waiting for the user's response! After the user
// sees the explanation, try again to request the permission.
//异步显示对用户的扩展* * *不阻止
//这个线程等待用户的响应！用户后
//参考解释，请再次请求许可。
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(thisActivity,
new String[]{Manifest.permission.READ_CONTACTS},
MY_PERMISSIONS_REQUEST_READ_CONTACTS);
// MY_PERMISSIONS_REQUEST_READ_CONTACTS is an
// app-defined int constant. The callback method gets the
// result of the request.
}
}
@Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_READ_CONTACTS: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted, yay! Do the
// contacts-related task you need to do.
} else {
// permission denied, boo! Disable the
// functionality that depends on this permission.
}
return;
}
// other 'case' lines to check for other
// permissions this app might request
}
}
总结
ContextCompat.checkSelfPermission(thisActivity, Manifest.permission.READ_CONTACTS) 判断是否有这个权限，有权限返回```PackageManager.PERMISSION_GRANTED``
shouldShowRequestPermissionRationale
onRequestPermissionsResult 在点击拒绝或者同意权限后回调
比较困惑的还是shouldShowRequestPermissionRationale根据方法得说明,翻译如下
*获取是否应该以请求请求的理由显示UI。
*只有在没有权限和上下文的情况下才应该这样做。
*请求的权限没有明确地传达给用户。
*授予这个权限会有什么好处。
*例如，如果您编写相机应用程序，请求相机许可
*将被用户预期，并且没有理由为什么它被请求是
*需要。然而，如果应用程序需要标记照片的位置，那么非技术。
*精明的用户可能想知道位置如何与拍照有关。在这种情况下
*您可以选择以请求此权限的理由来显示UI。
谷歌翻译如下
*获取您是否应该以请求许可的理由显示UI。
*只有在您没有权限和上下文的情况下，您才应该这样做
*所请求的许可不明确地与用户进行通信
*授予此权限会有什么好处。
* <p>
*例如，如果您编写相机应用程序，请求相机权限
*是用户期望的，并且没有理由说明它为什么被要求
*需要。但是，如果应用程序需要位置标记照片，然后是非技术
*精明的用户可能想知道拍摄地点与拍照有何关系。在这种情况下
*您可以选择以请求此权限的理由显示用户界面。
* Gets whether you should show UI with rationale for requesting a permission.
* You should do this only if you do not have the permission and the context in
* which the permission is requested does not clearly communicate to the user
* what would be the benefit from granting this permission.
* <p>
* For example, if you write a camera app, requesting the camera permission
* would be expected by the user and no rationale for why it is requested is
* needed. If however, the app needs location for tagging photos then a non-tech
* savvy user may wonder how location is related to taking photos. In this case
* you may choose to show UI with rationale of requesting this permission.
关键注释
@return Whether you can show permission rationale UI.
Whether you can show permission rationale UI.
你是否可以显示告知用户权限理由的界面 如果可以返回true
目标sdk低于23的体现
W/PermissionUtil: =========================================
W/PermissionUtil: checkSelfPermission:android.permission.SYSTEM_ALERT_WINDOW:未获得/拒绝
shouldShowRequestPermissionRationale:android.permission.SYSTEM_ALERT_WINDOW result不应该显示权限说明
W/PermissionUtil: requestPermissions:[android.permission.SYSTEM_ALERT_WINDOW] requestCode2
W/PermissionUtil: onRequestPermissionsResult: requestCode ,result:,grantResultslength:0
弹出系统对话框开始
E/AndroidRuntime: FATAL EXCEPTION: main
没有系统对话框权限shouldShowRequestPermissionRationale:android =false如果依然尝试申请，那么回调 onRequestPermissionsResult返回的结果数组长度为0 如果尝试弹出当然是崩溃
如果目标sdk大于等于23,结果 还是 直接 shouldShowRequestPermissionRationale:android false onRequestPermissionsResult有值，但是为0 ，换了2个手机都这样，有点崩溃，暂时放弃了，我有点怀疑小米和华为手机了.无论如何都不给弹出了，我卸载重装都这样，这不坑爹么
然后测试调用相机权限，成功弹出了，特么系统对话框的权限我突然想起来了，在高版本弹出系统对话框需要另外一种方式，叫启用应用上层显示的那种，这搞毛线，浪费我半天时间纠结了。
好了下面是我的日志调试工具
package cn.qssq666.robot.utils;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.pm.PackageManager;
import android.os.Build;
import android.support.annotation.NonNull;
import android.util.Log;
import android.view.WindowManager;
import java.util.Arrays;
/**
* Created by qssq on 2018/4/21 qssq666@foxmail.com
*/
public class PermissionUtil {
private static final String TAG = "PermissionUtil";
public static boolean debug=true;
public static void onRequestPermissionsResult(Activity activity, int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
Log.w(TAG, "onRequestPermissionsResult:" + " requestCode ,result:" + getPermissionsResultMsg(permissions, grantResults)+",grantResultslength:"+grantResults.length);
}
private static String getPermissionsResultMsg(String[] permissions, int[] grantResults) {
StringBuilder stringBuilder = new StringBuilder();
for (int i = 0; i < permissions.length; i++) {
stringBuilder.append(printPermission(permissions[i]) + ":" + getResultMsg(grantResults[i]) + "\n");
}
return stringBuilder.toString();
}
public static void requestPermissions(Activity activity, String[] permissions, int requestCode) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
activity.requestPermissions(permissions,requestCode);
Log.w(TAG, "requestPermissions:" + printPermissions(permissions) + " requestCode" + requestCode);
}else{
}
}
public static int checkSelfPermission(Activity activity, String permission) {
if(debug){
Log.w(TAG,"=========================================");
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
int i = activity.checkSelfPermission(permission);
if (debug) {
Log.w(TAG, "checkSelfPermission:" + printPermission(permission) + ":" + getResultMsg(i));
}
return i;
}
if (debug) {
Log.w(TAG, "Build.VERSION.SDK_INT <23 checkSelfPermission:" + printPermission(permission) + ":" + getResultMsg(PackageManager.PERMISSION_GRANTED));
}
return PackageManager.PERMISSION_GRANTED;
}
public static String printPermission(String permission) {
return permission;
}
public static String printPermissions(String[] permission) {
return Arrays.toString(permission);
}
/*
是否应该显示 请求权限信息
*/
public static boolean shouldShowRequestPermissionRationale(Activity activity, String permissionRationale) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
boolean result = activity.shouldShowRequestPermissionRationale(permissionRationale);
if (debug) {
Log.w(TAG, "shouldShowRequestPermissionRationale:" + printPermission(permissionRationale) + " result" + getRationaleResultMsg(result));
}
} else {
Log.w(TAG, "shouldShowRequestPermissionRationale <23 false" );
}
return false;
}
private static String getRationaleResultMsg(boolean result) {
return result ? "应该显示权限说明" : "不应该显示权限说明";
}
public static String getResultMsg(int permissionCode) {
if (permissionCode == PackageManager.PERMISSION_GRANTED) {
return "获得/成功";
} else {
return "未获得/拒绝";
}
}
public static void showSystemDialog(Activity mainActivity) {
if(debug){
Log.w(TAG,"弹出系统对话框开始");
AlertDialog.Builder builder = new AlertDialog.Builder(mainActivity);
builder.setMessage("我是系统对话框");
Dialog dialog= builder.create();
dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_DIALOG);
// dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);
dialog.show();
Log.w(TAG,"弹出系统对话框结束");
}
}
}
if (PermissionUtil.checkSelfPermission(this, Manifest.permission.SYSTEM_ALERT_WINDOW) == PackageManager.PERMISSION_GRANTED) {
registerWakeLock();
Log.w(TAG, "shouldShowRequestPermissionRationale not-call has granted permission");
} else {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (PermissionUtil.shouldShowRequestPermissionRationale(this,Manifest.permission.SYSTEM_ALERT_WINDOW)) {
Log.w(TAG, "shouldShowRequestPermissionRationale call");
PermissionUtil.requestPermissions(this,new String[]{Manifest.permission.SYSTEM_ALERT_WINDOW}, REQUEST_LOCK);
} else {
PermissionUtil.requestPermissions(this,new String[]{Manifest.permission.SYSTEM_ALERT_WINDOW}, REQUEST_LOCK);
Log.w(TAG, "shouldShowRequestPermissionRationale not-call");
}
} else {
Log.w(TAG, "low api not request permissions");
}
}最后附上官方的demo 地址https://github.com/googlesamples/android-RuntimePermissions/#readme 从下面代码可以看出来，思路是先检查权限，如果 没有获取到 就调用requestContactsPermissions 判断是否应该提示则返回true ，但是不过结果true or false 都调用了 下载demo 发现项目并不能编译，越来缺少了build.gradle 然后又发现缺少了design包然后又发现缺少了一个图片,经过修改正常运行，并且也能正常提示，所以这让我怀疑人生了额。
经过仔细思考发现清单文件是关键
下面是demo的部分代码
清单是必须填写的，不然低版本没法兼容的.
<!-- BEGIN_INCLUDE(manifest) -->
<!-- Note that all required permissions are declared here in the Android manifest.
On Android M and above, use of these permissions is only requested at run time. -->
<uses-permission android:name="android.permission.CAMERA" />
<!-- The following permissions are only requested if the device is on M or above.
On older platforms these permissions are not requested and will not be available. -->
<uses-permission-sdk-23 android:name="android.permission.READ_CONTACTS" />
<uses-permission-sdk-23 android:name="android.permission.WRITE_CONTACTS" />
.requestPermissions(MainActivity.this, PERMISSIONS_CONTACT,
REQUEST_CONTACTS);
在onRequestPermissionsResult判断操作结果, 成功则提示permision_available_camera的snackbar提示
if (grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// Camera permission has been granted, preview can be displayed
Log.i(TAG, "CAMERA permission has now been granted. Showing preview.");
Snackbar.make(mLayout, R.string.permision_available_camera,
Snackbar.LENGTH_SHORT).show();所有逻辑代码
/**
* Called when the 'show camera' button is clicked.
* Callback is defined in resource layout definition.
*/
public void showContacts(View v) {
Log.i(TAG, "Show contacts button pressed. Checking permissions.");
// Verify that all required contact permissions have been granted.
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_CONTACTS)
!= PackageManager.PERMISSION_GRANTED
|| ActivityCompat.checkSelfPermission(this, Manifest.permission.WRITE_CONTACTS)
!= PackageManager.PERMISSION_GRANTED) {
// Contacts permissions have not been granted.
Log.i(TAG, "Contact permissions has NOT been granted. Requesting permissions.");
requestContactsPermissions();
} else {
// Contact permissions have been granted. Show the contacts fragment.
Log.i(TAG,
"Contact permissions have already been granted. Displaying contact details.");
showContactDetails();
}
}
/**
* Requests the Contacts permissions.
* If the permission has been denied previously, a SnackBar will prompt the user to grant the
* permission, otherwise it is requested directly.
*/
private void requestContactsPermissions() {
// BEGIN_INCLUDE(contacts_permission_request)
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.READ_CONTACTS)
|| ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.WRITE_CONTACTS)) {
// Provide an additional rationale to the user if the permission was not granted
// and the user would benefit from additional context for the use of the permission.
// For example, if the request has been denied previously.
Log.i(TAG,
"Displaying contacts permission rationale to provide additional context.");
// Display a SnackBar with an explanation and a button to trigger the request.
Snackbar.make(mLayout, R.string.permission_contacts_rationale,
Snackbar.LENGTH_INDEFINITE)
.setAction(R.string.ok, new View.OnClickListener() {
@Override
public void onClick(View view) {
ActivityCompat
.requestPermissions(MainActivity.this, PERMISSIONS_CONTACT,
REQUEST_CONTACTS);
}
})
.show();
} else {
// Contact permissions have not been granted yet. Request them directly.
ActivityCompat.requestPermissions(this, PERMISSIONS_CONTACT, REQUEST_CONTACTS);
}
// END_INCLUDE(contacts_permission_request)
}
/**
* Callback received when a permissions request has been completed.
*/
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,
@NonNull int[] grantResults) {
if (requestCode == REQUEST_CAMERA) {
// BEGIN_INCLUDE(permission_result)
// Received permission result for camera permission.
Log.i(TAG, "Received response for Camera permission request.");
// Check if the only required permission has been granted
if (grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// Camera permission has been granted, preview can be displayed
Log.i(TAG, "CAMERA permission has now been granted. Showing preview.");
Snackbar.make(mLayout, R.string.permision_available_camera,
Snackbar.LENGTH_SHORT).show();
} else {
Log.i(TAG, "CAMERA permission was NOT granted.");
Snackbar.make(mLayout, R.string.permissions_not_granted,
Snackbar.LENGTH_SHORT).show();
}
// END_INCLUDE(permission_result)
} else if (requestCode == REQUEST_CONTACTS) {
Log.i(TAG, "Received response for contact permissions request.");
// We have requested multiple permissions for contacts, so all of them need to be
// checked.
if (PermissionUtil.verifyPermissions(grantResults)) {
// All required permissions have been granted, display contacts fragment.
Snackbar.make(mLayout, R.string.permision_available_contacts,
Snackbar.LENGTH_SHORT)
.show();
} else {
Log.i(TAG, "Contacts permissions were NOT granted.");
Snackbar.make(mLayout, R.string.permissions_not_granted,
Snackbar.LENGTH_SHORT)
.show();
}
} else {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
官方的demo 缺少了一个 build.gradle和一个图片，能不能修复看你们的本事了，我已经告诉你们了 哈哈，
apply plugin: 'com.android.application'
android {
compileSdkVersion 26
defaultConfig {
applicationId "com.example.android.system.runtimepermissions"
minSdkVersion 14
targetSdkVersion 27
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(include: ['*.jar'], dir: 'libs')
implementation 'com.android.support:appcompat-v7:27.1.0'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.1'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'
implementation 'com.android.support:design:27.1.0'
}
https://developer.android.com/training/permissions/requesting.htmlhttps://developer.android.google.cn/training/permissions/requesting.htmlhttps://www.jianshu.com/p/e1ab1a179fbb
