1.效果图
edittext-01.gif
2.效果分析
2.1扩大EditText的上下范围
2.2添加透明、不透明效果、添加向上向下效果
2.3添加方法，使调用者可以在代码中或者布局文件中启用关闭float TextView功能
3.具体实现
3.1 扩大EditText上下范围
image.png
public class cmMaterialEditTextView extends AppCompatEditText {
private static final String TAG = cmMaterialEditTextView.class.getSimpleName();
private static final float TEXT_SIZE = DpToPxUtil.dp2px(18);
private static final float TEXT_MARGIN = DpToPxUtil.dp2px(8);
private static final float TEXT_VERTRICAL_OFFSET = DpToPxUtil.dp2px(28);
private static final float TEXT_HORIZONTAL_OFFSET = DpToPxUtil.dp2px(5);
//画笔
private Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
{
//设置Padding
setPadding(getPaddingLeft(),(int) (getPaddingTop() + TEXT_SIZE + TEXT_MARGIN),getPaddingRight(),getPaddingBottom());
mPaint.setTextSize(TEXT_SIZE);
}
public cmMaterialEditTextView(Context context) {
super(context);
}
public cmMaterialEditTextView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public cmMaterialEditTextView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawText(getHint().toString(),TEXT_HORIZONTAL_OFFSET,TEXT_VERTRICAL_OFFSET,mPaint);
}
}
3.2 添加透明、不透明效果、添加向上向下效果
boolean floatingLabelShown = false;
float floatingLabelFraction;
public float getFloatingLabelFraction() {
return floatingLabelFraction;
}
public void setFloatingLabelFraction(float floatingLabelFraction) {
this.floatingLabelFraction = floatingLabelFraction;
invalidate();
}
addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
//隐藏
if(floatingLabelShown && TextUtils.isEmpty(s)){
ObjectAnimator animator1 = ObjectAnimator.ofFloat(cmMaterialEditTextView.this,"floatingLabelFraction",0);
animator1.start();
floatingLabelShown = false;
}else if(!floatingLabelShown && !TextUtils.isEmpty(s)){
ObjectAnimator animator2 = ObjectAnimator.ofFloat(cmMaterialEditTextView.this,"floatingLabelFraction",1);
animator2.start();
floatingLabelShown = true;
}
}
@Override
public void afterTextChanged(Editable s) {
}
});
3.3添加方法，使调用者可以在代码中或者布局文件中启用关闭float TextView功能
attrs文件中
public class cmMaterialEditTextView extends AppCompatEditText {
private static final String TAG = cmMaterialEditTextView.class.getSimpleName();
private static final float TEXT_SIZE = DpToPxUtil.dp2px(18);
private static final float TEXT_MARGIN = DpToPxUtil.dp2px(8);
private static final float TEXT_VERTRICAL_OFFSET = DpToPxUtil.dp2px(28);
private static final float TEXT_HORIZONTAL_OFFSET = DpToPxUtil.dp2px(5);
private static final float TEXT_ANIMATION_OFFSET = DpToPxUtil.dp2px(28);
ObjectAnimator animator;
boolean floatingLabelShown = false;
float floatingLabelFraction;
public float getFloatingLabelFraction() {
return floatingLabelFraction;
}
public void setFloatingLabelFraction(float floatingLabelFraction) {
this.floatingLabelFraction = floatingLabelFraction;
invalidate();
}
//画笔
private Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
//是否使用Floating Label
boolean userFloatingLabel;
Rect rectBackground = new Rect();
public void setUserFloatingLabel(boolean userFloatingLabel){
if(this.userFloatingLabel != userFloatingLabel){
this.userFloatingLabel = userFloatingLabel;
onUserFloationgLabel();
}
}
private void onUserFloationgLabel(){
getBackground().getPadding(rectBackground);
if(userFloatingLabel){
setPadding(rectBackground.left,(int) (rectBackground.top + TEXT_SIZE + TEXT_MARGIN),rectBackground.right,rectBackground.bottom);
}else{
setPadding(rectBackground.left,rectBackground.top,rectBackground.right,rectBackground.bottom);
}
}
private ObjectAnimator getAnimator() {
if(animator == null){
animator = ObjectAnimator.ofFloat(cmMaterialEditTextView.this,"floatingLabelFraction",0,1);
}
return animator;
}
public cmMaterialEditTextView(Context context) {
super(context);
}
public cmMaterialEditTextView(Context context, AttributeSet attrs) {
super(context, attrs);
initMaterialEditTextView(context,attrs);
}
public cmMaterialEditTextView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
private void initMaterialEditTextView(Context context, AttributeSet attrs) {
TypedArray typedArray = context.obtainStyledAttributes(attrs,R.styleable.cmMaterialEditTextView);
userFloatingLabel = typedArray.getBoolean(R.styleable.cmMaterialEditTextView_cmMaterialEditTextViewUserFloating,true);
typedArray.recycle();
mPaint.setTextSize(TEXT_SIZE);
//设置Padding
onUserFloationgLabel();
addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
if(userFloatingLabel){
//隐藏
if(floatingLabelShown && TextUtils.isEmpty(s)){
getAnimator().reverse();
floatingLabelShown = false;
}else if(!floatingLabelShown && !TextUtils.isEmpty(s)){
getAnimator().start();
floatingLabelShown = true;
}
}
}
@Override
public void afterTextChanged(Editable s) {
}
});
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
mPaint.setAlpha((int) (0xff * floatingLabelFraction));
float extraOffset = TEXT_ANIMATION_OFFSET * (1 - floatingLabelFraction);
canvas.drawText(getHint().toString(),TEXT_HORIZONTAL_OFFSET,TEXT_VERTRICAL_OFFSET + extraOffset,mPaint);
}
}
Demo：CMViewDemo Github地址