Question

我正在尝试在对话框中插入SeekBar来更改亮度。为此，我编写了这段代码。

public class Lum extends DialogFragment{


        private SeekBar brightbar;
        private int brightness;
        private ContentResolver cResolver;
        private Window window;
        TextView txtPerc;
        boolean stato;
        Context context;

        public android.app.Dialog onCreateDialog(Bundle savedInstanceState) {
            // Use the Builder class for convenient dialog construction

            AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());

            LayoutInflater inflater = getActivity().getLayoutInflater();
            View view = inflater.inflate(R.layout.dialog_brightness, null);
            builder.setView(view);

        brightbar = (SeekBar) view.findViewById(R.id.brightbar);
        txtPerc = (TextView) view.findViewById(R.id.txtPercentage);
        //cResolver = getContentResolver();
        //window = getWindow();
        brightbar.setMax(255);
        brightbar.setKeyProgressIncrement(1);

        brightbar = (SeekBar) view.findViewById(R.id.brightbar);
        txtPerc = (TextView) view.findViewById(R.id.txtPercentage);
        cResolver = getContentResolver();
        window = getWindow();
        brightbar.setMax(255);
        brightbar.setKeyProgressIncrement(1);

        try {
            brightness = Settings.System.getInt(context.getContentResolver(), Settings.System.SCREEN_BRIGHTNESS);
        } catch (SettingNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        float perc = (brightness /(float)255)*100;
        txtPerc.setText((int)perc +" %");

        brightbar.setProgress(brightness);
        brightbar.setOnSeekBarChangeListener(new OnSeekBarChangeListener()
        {
            public void onStopTrackingTouch(SeekBar seekBar)
            {
                Settings.System.putInt(context.getContentResolver(), Settings.System.SCREEN_BRIGHTNESS, brightness);
                LayoutParams layoutpars = window.getAttributes();
                layoutpars.screenBrightness = brightness / (float)255;
                window.setAttributes(layoutpars);
            }

            public void onStartTrackingTouch(SeekBar seekBar)
            {

            }

            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser)
            {


                    brightness = progress;

                    float perc = (brightness /(float)255)*100;
                    txtPerc.setText((int)perc +" %");
            }
        });     

            builder.setTitle("Brightness")
                   .setPositiveButton("Close", new DialogInterface.OnClickListener() {
                       public void onClick(DialogInterface dialog, int id) {
                           dismiss();
    }
                   });

            // Create the AlertDialog object and return it
            return builder.create();
        }
    }

问题是我的IDE Eclipse标记了getContentResolver和getWindow中的错误，因为我正在使用DialogFragment而不是Activity。如何在本课程中使用此说明？或者，如果你不能这样做，还有另一种选择吗？提前致谢

Answer 1

http://developer.android.com/reference/android/content/Context.html#getContentResolver()

getContentResolver()需要一个上下文。

你有context.getContentResolver()。使用getActivity().getContentResolver()。

http://developer.android.com/reference/android/app/Activity.html#getWindow()

同样使用getActivity().getWindow()

getActivity()

返回此片段当前与之关联的活动。

DialogFragment中的getContentResolver（）和getWindow（）

1 个答案: