Question

我的应用程序停止运行，我不明白为什么;我认为我的代码是正确的。它只是一个简单的CALL应用程序

Button b; 
Context= mContext;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    b = (Button) findViewById(R.id.call);
    b.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {

            if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) {
                Intent call = new Intent(Intent.ACTION_DIAL, Uri.parse("tel:0102030405"));
                startActivity(call);


                return;
            }

        }

        }

    );
}

Answer 1

将上下文初始化为mContext = getApplicationContext（）;在onCreate（）

中

Answer 2

如果未授予错误权限，则启动活动。在else部分中，一旦获得权限，写下要执行的代码。也将此作为上下文传递。

if (ContextCompat.checkSelfPermission(thisActivity,
                Manifest.permission.CALL_PHONE)
        != PackageManager.PERMISSION_GRANTED) {

    // Should we show an explanation?
    if (ActivityCompat.shouldShowRequestPermissionRationale(this,
            Manifest.permission.CALL_PHONE)) {

        // Show an explanation 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.

    } else {

        // No explanation needed, we can request the permission.

        ActivityCompat.requestPermissions(this,
                new String[]{Manifest.permission.CALL_PHONE},
                MY_PERMISSIONS_REQUEST_CALL_PHONE);


    }
} else {
 Intent call = new Intent(Intent.ACTION_DIAL, Uri.parse("tel:0102030405"));
                startActivity(call);

}



@Override
public void onRequestPermissionsResult(int requestCode,
        String permissions[], int[] grantResults) {
    switch (requestCode) {
        case MY_PERMISSIONS_REQUEST_CALL_PHONE: {
            // 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.
Intent call = new Intent(Intent.ACTION_DIAL, Uri.parse("tel:0102030405"));
                startActivity(call);
            } 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
    }
}

此外，将以下行添加到清单：

<uses-permission android:name="android.permission.CALL_PHONE"/>

Answer 3

示例代码

public class MainActivity extends AppCompatActivity {
        private EditText ed_call;
        private Button btn_call;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);

            ed_call = (EditText) findViewById(R.id.ed_call);
            btn_call = (Button) findViewById(R.id.btn_call);

            btn_call.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    try {
                        Intent callintent = new Intent(Intent.ACTION_CALL);
                        callintent.setData(Uri.parse("tel:" + ed_call.getText().toString()));
                        if (ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) {
                            // TODO: Consider calling
                            return;
                        }
                        startActivity(callintent);
                    } catch (Exception e) {
                        e.printStackTrace(); 
                    }
                }
            });
        }
}

<强> activity_main.xml中

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_margin="5dp"
    android:orientation="vertical"
    tools:context="com.example.actiondemo.MainActivity">
    <LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">
            <EditText
                android:id="@+id/ed_call"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
            <Button
                android:id="@+id/btn_call"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Call" />
    </LinearLayout>
</LinearLayout>

这可以帮助你。

我的通话应用程序停止运行，我没有任何代码错误

3 个答案: