一行代码使TextView变成打字机模式或更改字体。

扯蛋：玩过《开眼》APP的都知道，里面几乎所有的TextView都是类似于打字机模式。本文是采用RXjava2几行代码实现了打字机功能，外加自定义了字体

• 效果图

• github欢迎start 支持: https://github.com/KomoriWu/TypeWriter.git

• 具有TextView本身所有的属性

• 自定义的属性有

<declare-styleable name="TypeWrite">        //设置打字机速度(毫秒不能为0)        <attr name="setSpeed" format="integer" />        //是否设置字体        <attr name="isEnableTtf" format="boolean" />        //是否开启打字机模式        <attr name="isEnableTypeWrite" format="boolean" />    </declare-styleable>

项目中引用：

Step 1. Add the JitPack repository to your build file

allprojects {        repositories {            maven { url 'https://jitpack.io' }        }    }

Step 2. Add the dependency

dependencies {          compile 'com.github.KomoriWu:TypeWriter:1.0'    }

Step 3.布局中引用

 <com.komoriwu.typewriter.TypeWriteTextView        android:id="@+id/tv"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="@string/hint"        android:textColor="@color/colorAccent"        android:textSize="20sp"        custom:setSpeed="100"        custom:isEnableTtf="true"        custom:isEnableTypeWrite="true"/>

源码：

源码很简单，想自定义的，直接拷贝加以修改即可。

public class TypeWriteTextView extends TextView {    public static final int UPDATE_DELAY = 10;    private String mTextStr;    private int mLength;    private int mIndex;    public TypeWriteTextView(Context context) {        super(context);        init(context, null, 0);    }    public TypeWriteTextView(Context context, @Nullable AttributeSet attrs) {        super(context, attrs);        init(context, attrs, 0);    }    public TypeWriteTextView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {        super(context, attrs, defStyleAttr);        init(context, attrs, defStyleAttr);    }    private void init(Context context, AttributeSet attrs, int defStyleAttr) {        mTextStr = (String) getText();        mLength = mTextStr.length();        int speed = 100;        boolean isEnableTypeWrite = true;        boolean isEnableTtf = true;        if (attrs != null) {            TypedArray typedArray = context.getTheme().                    obtainStyledAttributes(attrs, R.styleable.TypeWrite, defStyleAttr, 0);            int n = typedArray.getIndexCount();            for (int i = 0; i < n; i++) {                int attr = typedArray.getIndex(i);                switch (attr) {                    case R.styleable.TypeWrite_setSpeed:                        speed = typedArray.getInteger(attr, 100);                        break;                    case R.styleable.TypeWrite_isEnableTypeWrite:                        isEnableTypeWrite = typedArray.getBoolean(attr, true);                        break;                    case R.styleable.TypeWrite_isEnableTtf:                        isEnableTtf = typedArray.getBoolean(attr, true);                        break;                }            }            typedArray.recycle();        }        if (isEnableTtf) {            String fontName = "Heavy.ttf";            super.setTypeface(Typeface.createFromAsset(getContext().getAssets(),                    "fonts/" + fontName), defStyleAttr);        }        if (isEnableTypeWrite) {            Flowable.interval(UPDATE_DELAY, speed, TimeUnit.MILLISECONDS)                    .take(mLength + 1)                    .map(new Function<Long, String>() {                        @Override                        public String apply(Long aLong) throws Exception {                            return mTextStr.substring(0, mIndex);                        }                    })                    .subscribeOn(Schedulers.io())                    .observeOn(AndroidSchedulers.mainThread())                    .subscribe(new Consumer<String>() {                        @Override                        public void accept(String str) throws Exception {                            mIndex++;                            setText(str);                        }                    });        }    }}

• github欢迎start 支持: https://github.com/KomoriWu/TypeWriter.git