Android: set view style programmatically

问题:

Here\'s XML:

<RelativeLayout 
    xmlns:android=\"http://schemas.android.com/apk/res/android\"
    style=\"@style/LightStyle\"
    android:layout_width=\"fill_parent\"
    android:layout_height=\"55dip\"
    android:clickable=\"true\"
    android:orientation=\"horizontal\" >

    <LinearLayout
        android:layout_width=\"match_parent\"
        android:layout_height=\"match_parent\"
        android:orientation=\"horizontal\" />

</RelativeLayout>

How to set style attribute programmatically?

回答1:

Technically you can apply styles programmatically, with custom views anyway:

private MyRelativeLayout extends RelativeLayout {
  public MyRelativeLayout(Context context) {
     super(context, null, R.style.LightStyle);
  }
}

The one argument constructor is the one used when you instantiate views programmatically.

So chain this constructor to the super that takes a style parameter.

RelativeLayout someLayout = new MyRelativeLayout(context);

---

Or as @Dori pointed out simply:

RelativeLayout someLayout = new RelativeLayout(context, null, R.style.LightStyle);

回答2:

What worked for me:

Button b = new Button(new ContextThemeWrapper(this, R.style.ButtonText), null, 0);

• Use a ContextThemeWrapper

AND

• Use the 3-arguments constructor (won\'t work without this)

回答3:

You cannot set a view\'s style programmatically yet, but you may find this thread useful.

Update: At the time of answering this question (mid 2012, API level 14-15), setting the view programmatically was not an option (even though there were some non-trivial workarounds)whereas this has been made possible after the more recent API releases. See @Blundell\'s answer for details.

回答4:

You can apply a style to your activity by doing:

super.setTheme( R.style.MyAppTheme );

or Android default:

super.setTheme( android.R.style.Theme );

in your activity, before setContentView().

回答5:

For a new Button/TextView:

Button mMyButton = new Button(new ContextThemeWrapper(this, R.style.button_disabled), null, 0);

For an existing instance:

mMyButton.setTextAppearance(this, R.style.button_enabled);

For Image or layouts:

Image mMyImage = new ImageView(new ContextThemeWrapper(context, R.style.article_image), null, 0);

回答6:

Non of the provided answers are correct.

You CAN set style programatically.

Short answer is take a look at http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/5.1.1_r1/android/content/Context.java#435

Long answer. Here\'s my snippet to set custom defined style programatically to your view:

1) Create a style in your styles.xml file

 <style name=\"MyStyle\">
    <item name=\"customTextColor\">#39445B</item>
    <item name=\"customDividerColor\">#8D5AA8</item>
</style>

Do not forget to define your custom attributes in attrs.xml file

My attrsl.xml file:

<declare-styleable name=\"CustomWidget\">
    <attr name=\"customTextColor\" format=\"color\" />
    <attr name=\"customDividerColor\" format=\"color\" />
</declare-styleable>

Notice you can use any name for your styleable (my CustomWidget)

Now lets set the style to the widget Programatically Here\'s My simple widget:

public class StyleableWidget extends LinearLayout {

private final StyleLoader styleLoader = new StyleLoader();

private TextView textView;
private View divider;

public StyleableWidget(Context context) {
    super(context);
    init();
}

private void init() {
    inflate(getContext(), R.layout.widget_styleable, this);
    textView = (TextView) findViewById(R.id.text_view);
    divider = findViewById(R.id.divider);
    setOrientation(VERTICAL);
}

protected void apply(StyleLoader.StyleAttrs styleAttrs) {
    textView.setTextColor(styleAttrs.textColor);
    divider.setBackgroundColor(styleAttrs.dividerColor);
}

public void setStyle(@StyleRes int style) {
    apply(styleLoader.load(getContext(), style));
}
}

layout:

<TextView
    android:id=\"@+id/text_view\"
    android:layout_width=\"wrap_content\"
    android:layout_height=\"wrap_content\"
    android:textSize=\"22sp\"
    android:layout_gravity=\"center\"
    android:text=\"@string/styleble_title\" />

<View
    android:id=\"@+id/divider\"
    android:layout_width=\"match_parent\"
    android:layout_height=\"1dp\"/>

</merge>

And finally StyleLoader class implementation

public class StyleLoader {

public StyleLoader() {

}

public static class StyleAttrs {
    public int textColor;
    public int dividerColor;
}

public StyleAttrs load(Context context, @StyleRes int styleResId) {
    final TypedArray styledAttributes = context.obtainStyledAttributes(styleResId, R.styleable.CustomWidget);
    return load(styledAttributes);
}

@NonNull
private StyleAttrs load(TypedArray styledAttributes) {
    StyleAttrs styleAttrs = new StyleAttrs();
    try {
        styleAttrs.textColor = styledAttributes.getColor(R.styleable.CustomWidget_customTextColor, 0);
        styleAttrs.dividerColor = styledAttributes.getColor(R.styleable.CustomWidget_customDividerColor, 0);
    } finally {
        styledAttributes.recycle();
    }
    return styleAttrs;
}
}

You can find fully working example at https://github.com/Defuera/SetStylableProgramatically

回答7:

If you\'d like to continue using XML (which the accepted answer doesn\'t let you do) and set the style after the view has been created you may be able to use the Paris library which supports a subset of all available attributes.

Since you\'re inflating your view from XML you\'d need to specify an id in the layout:

<RelativeLayout 
    xmlns:android=\"http://schemas.android.com/apk/res/android\"
    android:id=\"@+id/my_styleable_relative_layout\"
    style=\"@style/LightStyle\"
    ...

Then when you need to change the style programmatically, after the layout has been inflated:

// Any way to get the view instance will do
RelativeLayout myView = findViewById(R.id.my_styleable_relative_layout);

// This will apply all the supported attribute values of the style
Paris.style(myView).apply(R.style.LightStyle);

For more: the list of supported view types and attributes (includes background, padding, margin, etc. and can easily be extended) and installation instructions with additional documentation.

Disclaimer: I\'m the original author of said library.

回答8:

I used views defined in XML in my composite ViewGroup, inflated them added to Viewgroup. This way I cannot dynamically change style but I can make some style customizations. My composite:

public class CalendarView extends LinearLayout {

private GridView mCalendarGrid;
private LinearLayout mActiveCalendars;

private CalendarAdapter calendarAdapter;

public CalendarView(Context context) {
    super(context);

}

public CalendarView(Context context, AttributeSet attrs) {
    super(context, attrs);

}

@Override
protected void onFinishInflate() {
    super.onFinishInflate();
    init();
}

private void init() {
    mCalendarGrid = (GridView) findViewById(R.id.calendarContents);
    mCalendarGrid.setNumColumns(CalendarAdapter.NUM_COLS);

    calendarAdapter = new CalendarAdapter(getContext());
    mCalendarGrid.setAdapter(calendarAdapter);
    mActiveCalendars = (LinearLayout) findViewById(R.id.calendarFooter);
}

}

and my view in xml where i can assign styles:

<com.mfitbs.android.calendar.CalendarView
xmlns:android=\"http://schemas.android.com/apk/res/android\"
android:id=\"@+id/calendar\"
android:layout_width=\"match_parent\"
android:layout_height=\"wrap_content\"
android:layout_gravity=\"center_horizontal\"
android:orientation=\"vertical\"
>

<GridView
    android:id=\"@+id/calendarContents\"
    android:layout_width=\"match_parent\"
    android:layout_height=\"wrap_content\" />

<LinearLayout
    android:id=\"@+id/calendarFooter\"
    android:layout_width=\"match_parent\"
    android:layout_height=\"wrap_content\"
    android:orientation=\"horizontal\"
    />

回答9:

This is my simple example, the key is the ContextThemeWrapper wrapper, without it, my style does not work, and using the three parameters constructor of the View.

ContextThemeWrapper themeContext = new ContextThemeWrapper(this, R.style.DefaultLabelStyle);
TextView tv = new TextView(themeContext, null, 0);
tv.setText(\"blah blah ...\");
layout.addView(tv);

回答10:

I don\'t propose to use ContextThemeWrapper as it do this:

    The specified theme will be applied on top of 
    the base context\'s theme.

What can make unwanted results in your application. Instead I propose new library \"paris\" for this from airbnb guys:

https://github.com/airbnb/paris

Define and apply styles to Android views programmatically

回答11:

You can create the xml containing the layout with the desired style and then change the background resource of your view, like this.