简单的主题白天夜间切换

1：在 style中添加黑夜主题

<!--白天主题--> 这个主题是每个项目就自带的主题默认是白天主题

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">

<item name="colorPrimary">@color/colorPrimary</item>

<item name="colorPrimaryDark">@color/colorPrimaryDark</item>

<item name="colorAccent">@color/colorAccent</item>

</style>

<!--黑夜主题-->

<style name="AppTheme.Black" parent="Theme.AppCompat">

</style>

2：添加到res目录下创建一个anim文件夹

activity_out.xml

<?xml version="1.0" encoding="utf-8"?>

<set xmlns:android="http://schemas.android.com/apk/res/android">

<alpha

android:duration="0"

android:fromAlpha="1.0"

android:interpolator="@android:anim/decelerate_interpolator"

android:toAlpha="0.0">

</alpha>

</set>

activity_in.xml

<?xml version="1.0" encoding="utf-8"?>

<set xmlns:android="http://schemas.android.com/apk/res/android">

<alpha

android:duration="0"

android:fromAlpha="0.0"

android:interpolator="@android:anim/accelerate_interpolator"

android:toAlpha="1.0">

</alpha>

</set>

3：创建Preferences和UiUtils类

Preferences

public class Preferences {

private static final String shared_name="user_guide";

private static SharedPreferences sp;

public static String getString(Context context, String key,

String defaultValues) {

SharedPreferences sp = context.getSharedPreferences(shared_name,

context.MODE_PRIVATE);

return sp.getString(key, defaultValues);

}

public static void setString(Context context, String key, String Values) {

SharedPreferences sp = context.getSharedPreferences(shared_name,

context.MODE_PRIVATE);

sp.edit().putString(key, Values).commit();

}

}

UiUtils

public class UiUtils {

//获取主题

public static int getAppTheme(Context ctx) {

String value = Preferences.getString(ctx, "activity_theme", "1");

switch (Integer.valueOf(value)) {

case 1:

return R.style.AppTheme;//白色主题

case 2:

return R.style.AppTheme_Black;

default:

return R.style.AppTheme;//默认白色

}

}

//切换主题

//当然也可以使用资源ID来进行标记

public static void switchAppTheme( Context ctx){

String value = Preferences.getString(ctx, "activity_theme", "1");

switch (Integer.valueOf(value)){

case 1:

Preferences.setString(ctx, "activity_theme", "2");

break;

case 2:

Preferences.setString(ctx, "activity_theme", "1");

break;

default:

Preferences.setString(ctx, "activity_theme", "1");

break;

}

}

}

主Activity

public class MainActivity extends AppCompatActivity {

private int theme = 0;

@Override

protected void onCreate(Bundle savedInstanceState) {

//切换主题必须放在onCreate()之前

if (savedInstanceState == null) {

theme = UiUtils.getAppTheme(MainActivity.this);

} else {

theme = savedInstanceState.getInt("theme");

}

setTheme(theme);

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

}

public void click(View v) {

UiUtils.switchAppTheme(MainActivity.this);

reload();

}

public void reload() {

Intent intent = getIntent();

overridePendingTransition(R.anim.activity_in, R.anim.activity_out);//进入动画

finish();

overridePendingTransition(R.anim.activity_in, R.anim.activity_out);

startActivity(intent);

}

}