今天在学习自定义View当中遇到了一个Typeface属性,所以遇见问题,就学习一下。
Android 自带字体有四种属性:“sans”, “serif”, “monospace","normal"
第一种通过xml属性去设置:
android:typeface="monospace" //sans,serif,normal
第二种通过java代码去设置:
①第一种构造方法
view.setTypeface(typeface,typefaceStyle);
属性不明白看源码:
/**
* Sets the typeface and style in which the text should be displayed,
* and turns on the fake bold and italic bits in the Paint if the
* Typeface that you provided does not have all the bits in the
* style that you specified.
*
* @attr ref android.R.styleable#TextView_typeface
* @attr ref android.R.styleable#TextView_textStyle
*/
public void setTypeface(Typeface tf, int style) {
if (style > 0) {
if (tf == null) {
tf = Typeface.defaultFromStyle(style);
} else {
tf = Typeface.create(tf, style);
}
setTypeface(tf);
// now compute what (if any) algorithmic styling is needed
int typefaceStyle = tf != null ? tf.getStyle() : 0;
int need = style & ~typefaceStyle;
mTextPaint.setFakeBoldText((need & Typeface.BOLD) != 0);
mTextPaint.setTextSkewX((need & Typeface.ITALIC) != 0 ? -0.25f : 0);
} else {
mTextPaint.setFakeBoldText(false);
mTextPaint.setTextSkewX(0);
setTypeface(tf);
}
}
两个参数含义:
typeface,就是一个Typeface 对象。 可以传空对象,若空对象就是走默认style
style,Typeface.NORMAL int值。
②另一个构造方法:
可以设置自定义的字体,对于在Android中引入其他字体,
要将字体文件保存在assets/fonts/目录下,字体文件有*.ttf和*.otf等格式
view.setTypeface(typeface);
Typeface typeface;
typeface = Typeface.createFromAsset(getAssets(), "fonts/regular.otf");//可以从assets中放入我们的自定义字体属性。
view.setTypeface(typeface);
看源码:
/**
* Sets the typeface and style in which the text should be displayed.
* Note that not all Typeface families actually have bold and italic
* variants, so you may need to use
* {@link #setTypeface(Typeface, int)} to get the appearance
* that you actually want.
*
* @see #getTypeface()
*
* @attr ref android.R.styleable#TextView_fontFamily
* @attr ref android.R.styleable#TextView_typeface
* @attr ref android.R.styleable#TextView_textStyle
*/
public void setTypeface(Typeface tf) {
if (mTextPaint.getTypeface() != tf) {
mTextPaint.setTypeface(tf);//给绘制TextView的画笔,设置字体属性
if (mLayout != null) {//如果布局不为空
nullLayouts();
requestLayout();//刷新layout
invalidate();//刷新View控件
}
}
}
关于自定义的Android字体,在加载的过程中由于文件的大小可能会影响App性能,
可以把加载字体放在App启动时候去加载,把Typeface设成static,使用的时候直接调用即可。
关于fount文件里的字体,我们只需要添加我们用到的字体,防止文件太大,加载过慢。