Android Studio 学习（六）内容提供器

运行时权限

• 使用ContextCompat.checkSelfPermission(MainActivity.this,Manifest.permission.CALL_PHONE)!=PackageManager.PERMISSION_GRANTED//判断是否有权限
• ActivityCompat.requestPermissions(MainActivity.this,
  
  new String[] {Manifest.permission.CALL_PHONE},1);//没有权限 进行申请
• onRequestPermissionResult() //无论哪种结果都会回调到这个函数中 所以重写这个函数

makecallButton.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

if(ContextCompat.checkSelfPermission(MainActivity.this, Manifest.

permission.CALL_PHONE)!=PackageManager.PERMISSION_GRANTED)

ActivityCompat.requestPermissions(MainActivity.this,

new String[] {Manifest.permission.CALL_PHONE},1);

else

call();

}

});

private void call()

{

try{

Intent intent = new Intent (Intent.ACTION_CALL);

intent.setData(Uri.parse("tel:10086"));

startActivity(intent);

}

catch (SecurityException e)

{

e.printStackTrace();

}

}

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    switch (requestCode){
    case 1:
        if(grantResults.length >0 && grantResults[0]== PackageManager.PERMISSION_GRANTED)
            call();
        else
            Toast.makeText(MainActivity.this,"you denied the  permission",Toast.LENGTH_LONG).show();
        break;
    default:
}
}

}

查找联系人姓名和电话

ListView contactsView = (ListView) findViewById(R.id.listview);

adapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1,contactsList);

contactsView.setAdapter(adapter);

if(ContextCompat.checkSelfPermission(this,Manifest.permission.READ_CONTACTS)!=

PackageManager.PERMISSION_GRANTED)

ActivityCompat.requestPermissions(this,new String[]{Manifest.permission

.READ_CONTACTS},2);

else {

readContanct();

}

private void readContanct()

{

Cursor cursor = null;

try{

cursor = getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI,

null,null,null,null);

if(cursor != null)

while (cursor.moveToNext()){

String displayName = cursor.getString(cursor.getColumnIndex

(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));

String number =cursor.getColumnName(cursor.getColumnIndex

(ContactsContract.CommonDataKinds.Phone.NUMBER));

contactsList.add(number);

adapter.notifyDataSetChanged();

}

}

catch (Exception e)

{

e.printStackTrace();

}

finally {

if(cursor!=null)

cursor.close();

}

}