Question

我有两项活动。一个是主要活动，另一个是设置活动。

当用户从颜色选择器对话框中选择颜色时，我想从设置活动中更改主题。

现在我可以更改主题，但它只能更改设置活动的主题，而不是主要活动。如何将主题设置为主要活动？

设置活动：

public class Settings extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {


          Theme.onActivityCreateSetTheme(this);

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_settings);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);


    sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);



    final ColorPickerDialog colorPickerDialog = new ColorPickerDialog();
    colorPickerDialog.initialize(R.string.dialog_title, new int[]{Color.CYAN, Color.LTGRAY, Color.BLACK, Color.BLUE, Color.GREEN, Color.MAGENTA, Color.RED, Color.GRAY, Color.YELLOW}, Color.YELLOW, 3, 2);
    colorPickerDialog.setOnColorSelectedListener(new ColorPickerSwatch.OnColorSelectedListener() {

        @Override
        public void onColorSelected(int color) {



            //  startActivityForResult(new Intent(getApplicationContext(),
            //         ThemedPreferenceActivity.class), SETTINGS_ACTION);

            if (color == Color.CYAN) {
                Theme.changeToTheme(Settings.this, Theme.THEME_DEFAULT);
                no = 0;
            }
            else if (color == Color.LTGRAY)

            {
                Theme.changeToTheme(Settings.this, Theme.THEME_WHITE);
                no = 1;
            }
            else if (color == Color.BLACK) {

                Theme.changeToTheme(Settings.this,Theme.THEME_BLUE);
                no = 3;

            }
            Toast.makeText(Settings.this, "selectedColor : " + color, Toast.LENGTH_SHORT).show();
        }

    });



    SharedPreferences.Editor editor = sharedpreferences.edit();

    editor.putInt("color_1",no);
    editor.putInt("color_2",no);
    editor.putInt("color_3",no);
    editor.commit();

    LinearLayout theme = (LinearLayout)findViewById(R.id.theme);

    theme.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            colorPickerDialog.show(getSupportFragmentManager(), "colorpicker");
        }
    });


}

主题：

 public class Theme {

    private static int sTheme;

    public final static int THEME_DEFAULT = 0;
    public final static int THEME_WHITE = 1;
    public final static int THEME_BLUE = 2;

    /** * Set the theme of the Activity, and restart it by creating a new Activity of the same type. */
    public static void changeToTheme(Activity activity, int theme) {
        sTheme = theme; activity.finish();

  activity.startActivity(new Intent(activity, activity.getClass()));
    }

    /** Set the theme of the activity, according to the configuration. */
    public static void onActivityCreateSetTheme(Activity activity) {
        switch (sTheme) {
            default: case THEME_DEFAULT:
                activity.setTheme(R.style.BlueTheme);
                break;
        }
    }
}

编辑：

主要活动：

  @Override
protected void onCreate(Bundle savedInstanceState) {

    SharedPreferences pref = getApplicationContext().getSharedPreferences("MyPref", MODE_PRIVATE);
    SharedPreferences.Editor editor = pref.edit();


    no = pref.getInt("color_1", 0);        
    no = pref.getInt("color_2", 0);
    no = pref.getInt("color_3", 0);

    if(no == 0)
    {
        setTheme(R.style.AppTheme);
    }

    else if(no == 1)
    {
        setTheme(R.style.AppTheme_Solarized);
    }

    else if(no == 2)
    {
        setTheme(R.style.BlueTheme);
    }


    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

谢谢..

Answer 1

     public void updateTheme(int themeID) {
        setTheme(themeID);
         Intent intent = getIntent();
        intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
        finish();
        overridePendingTransition(0, 0);
        startActivity(intent);
        overridePendingTransition(0, 0);
    }

Answer 2

除非重新启动当前活动，否则无法动态更改主题。

您可以使用两种方法解决问题：

在设置内容视图之前存储onCreate of activity检查从首选项共享数据并相应地设置主题。从设置活动设置共享数据。在 MainActivity 中检查共享数据。

public void onCreate(Bundle savedInstanceState)
{
    if (checkColorData("navcolor").equals("SomeColor"))
    {
        setTheme(R.style.AppTheme);
    }
    else
    {
        setTheme(R.style.AppThemeDarkNav);
    }
}

使用工具栏的工具栏并使用一些颜色可变的视图，您可以通过调用 setBackgoundColor

如何从另一个活动中将主题设置为主要活动？

2 个答案: