// Java
String mobileNumber = "99XXXXXXXX";
Intent intent = new Intent();
intent.setAction(Intent.ACTION_DIAL); // Action for what intent called for
intent.setData(Uri.parse("tel: " + mobileNumber)); // Data with intent respective action on intent
startActivity(intent);

// Kotlin
val mobileNumber = "99XXXXXXXX"
val intent = Intent()
intent.action = Intent.ACTION_DIAL // Action for what intent called for
intent.data = Uri.parse("tel: $mobileNumber") // Data with intent respective action on intent
startActivity(intent)

AndroidManifest.xml中的权限

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

完整的代码:

private void onCallBtnClick(){
    if (Build.VERSION.SDK_INT < 23) {
        phoneCall();
    }else {

        if (ActivityCompat.checkSelfPermission(mActivity,
                Manifest.permission.CALL_PHONE) == PackageManager.PERMISSION_GRANTED) {

            phoneCall();
        }else {
            final String[] PERMISSIONS_STORAGE = {Manifest.permission.CALL_PHONE};
            //Asking request Permissions
            ActivityCompat.requestPermissions(mActivity, PERMISSIONS_STORAGE, 9);
        }
    }
}

@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
    boolean permissionGranted = false;
    switch(requestCode){
        case 9:
            permissionGranted = grantResults[0]== PackageManager.PERMISSION_GRANTED;
            break;
    }
    if(permissionGranted){
        phoneCall();
    }else {
        Toast.makeText(mActivity, "You don't assign permission.", Toast.LENGTH_SHORT).show();
    }
}

private void phoneCall(){
    if (ActivityCompat.checkSelfPermission(mActivity,
            Manifest.permission.CALL_PHONE) == PackageManager.PERMISSION_GRANTED) {
        Intent callIntent = new Intent(Intent.ACTION_CALL);
        callIntent.setData(Uri.parse("tel:12345678900"));
        mActivity.startActivity(callIntent);
    }else{
        Toast.makeText(mActivity, "You don't assign permission.", Toast.LENGTH_SHORT).show();
    }
}

从拨号器调用(不需要权限):

   fun callFromDailer(mContext: Context, number: String) {
        try {
            val callIntent = Intent(Intent.ACTION_DIAL)
            callIntent.data = Uri.parse("tel:$number")
            mContext.startActivity(callIntent)
        } catch (e: Exception) {
            e.printStackTrace()
            Toast.makeText(mContext, "No SIM Found", Toast.LENGTH_LONG).show()
        }
    }

从应用程序直接呼叫(需要权限):

  fun callDirect(mContext: Context, number: String) {
        try {
            val callIntent = Intent(Intent.ACTION_CALL)
            callIntent.data = Uri.parse("tel:$number")
            mContext.startActivity(callIntent)
        } catch (e: SecurityException) {
            Toast.makeText(mContext, "Need call permission", Toast.LENGTH_LONG).show()
        } catch (e: Exception) {
            e.printStackTrace()
            Toast.makeText(mContext, "No SIM Found", Toast.LENGTH_LONG).show()
        }
    }

许可:

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

你可以使用Intent。ACTION_DIAL代替Intent.ACTION_CALL。这将显示已输入号码的拨号器，但允许用户决定是否实际拨打电话。ACTION_DIAL不需要CALL_PHONE权限。

这个演示对你有帮助…

在呼叫按钮上单击:

Intent intent = new Intent(Intent.ACTION_CALL, Uri.parse("tel:" + "Your Phone_number"));
startActivity(intent);

舱单许可:

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

2021年编辑

你应该把它写在你的清单文件，但同时你应该在运行时问。像这样的代码:

if (ContextCompat.checkSelfPermission(this,android.Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(this, arrayOf(android.Manifest.permission.CALL_PHONE),
                REQUEST_CODE)

        } else {

// else block means user has already accepted.And make your phone call here.

}

如果你想，你可以覆盖onRequestPermissionsResult给用户更好的体验，如果你写相同的代码与else块在这里，你的用户将不需要再次点击你的按钮，在你给予权限后，它将直接调用。

清单中的请求权限

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

调用使用此代码

Intent in = new Intent(Intent.ACTION_CALL, Uri.parse("tel:99xxxxxxxx"));
try {
    startActivity(in);
} catch (android.content.ActivityNotFoundException ex) {
    Toast.makeText(mcontext, "Could not find an activity to place the call.", Toast.LENGTH_SHORT).show();
}