Android自定义View实现垂直时间轴布局

<?xml version="1.0" encoding="utf-8"?> <resources>   <declare-styleable name="TimelineLayout">     <!--时间轴左偏移值-->     <attr name="line_margin_left" format="dimension"/>     <!--时间轴上偏移值-->     <attr name="line_margin_top" format="dimension"/>     <!--线宽-->     <attr name="line_stroke_width" format="dimension"/>     <!--线的颜色-->     <attr name="line_color" format="color"/>     <!--点的大小-->     <attr name="point_size" format="dimension"/>     <!--点的颜色-->     <attr name="point_color" format="color"/>     <!--图标-->     <attr name="icon_src" format="reference"/>   </declare-styleable> </resources> 

package com.jackie.timeline;  import android.content.Context; import android.content.res.TypedArray; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.drawable.BitmapDrawable; import android.support.annotation.Nullable; import android.util.AttributeSet; import android.view.View; import android.widget.LinearLayout;  /**  * Created by Jackie on 2017/3/8.  * 时间轴控件  */  public class TimelineLayout extends LinearLayout {   private Context mContext;    private int mLineMarginLeft;   private int mLineMarginTop;   private int mLineStrokeWidth;   private int mLineColor;;   private int mPointSize;   private int mPointColor;   private Bitmap mIcon;    private Paint mLinePaint; //线的画笔   private Paint mPointPaint; //点的画笔       //第一个点的位置   private int mFirstX;   private int mFirstY;   //最后一个图标的位置   private int mLastX;   private int mLastY;    public TimelineLayout(Context context) {     this(context, null);   }    public TimelineLayout(Context context, @Nullable AttributeSet attrs) {     this(context, attrs, 0);   }    public TimelineLayout(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {     super(context, attrs, defStyleAttr);     TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.TimelineLayout);     mLineMarginLeft = ta.getDimensionPixelOffset(R.styleable.TimelineLayout_line_margin_left, 10);     mLineMarginTop = ta.getDimensionPixelOffset(R.styleable.TimelineLayout_line_margin_top, 0);     mLineStrokeWidth = ta.getDimensionPixelOffset(R.styleable.TimelineLayout_line_stroke_width, 2);     mLineColor = ta.getColor(R.styleable.TimelineLayout_line_color, 0xff3dd1a5);     mPointSize = ta.getDimensionPixelSize(R.styleable.TimelineLayout_point_size, 8);     mPointColor = ta.getDimensionPixelOffset(R.styleable.TimelineLayout_point_color, 0xff3dd1a5);      int iconRes = ta.getResourceId(R.styleable.TimelineLayout_icon_src, R.drawable.ic_ok);     BitmapDrawable drawable = (BitmapDrawable) context.getResources().getDrawable(iconRes);     if (drawable != null) {       mIcon = drawable.getBitmap();     }      ta.recycle();      setWillNotDraw(false);     initView(context);   }    private void initView(Context context) {     this.mContext = context;      mLinePaint = new Paint();     mLinePaint.setAntiAlias(true);     mLinePaint.setDither(true);     mLinePaint.setColor(mLineColor);     mLinePaint.setStrokeWidth(mLineStrokeWidth);     mLinePaint.setStyle(Paint.Style.FILL_AND_STROKE);      mPointPaint = new Paint();     mPointPaint.setAntiAlias(true);     mPointPaint.setDither(true);     mPointPaint.setColor(mPointColor);     mPointPaint.setStyle(Paint.Style.FILL);   }    @Override   protected void onDraw(Canvas canvas) {     super.onDraw(canvas);          drawTimeline(canvas);   }    private void drawTimeline(Canvas canvas) {     int childCount = getChildCount();      if (childCount > 0) {       if (childCount > 1) {         //大于1，证明至少有2个，也就是第一个和第二个之间连成线，第一个和最后一个分别有点和icon         drawFirstPoint(canvas);         drawLastIcon(canvas);         drawBetweenLine(canvas);       } else if (childCount == 1) {         drawFirstPoint(canvas);       }     }   }    private void drawFirstPoint(Canvas canvas) {     View child = getChildAt(0);     if (child != null) {       int top = child.getTop();       mFirstX = mLineMarginLeft;       mFirstY = top + child.getPaddingTop() + mLineMarginTop;        //画圆       canvas.drawCircle(mFirstX, mFirstY, mPointSize, mPointPaint);     }   }    private void drawLastIcon(Canvas canvas) {     View child = getChildAt(getChildCount() - 1);     if (child != null) {       int top = child.getTop();       mLastX = mLineMarginLeft;       mLastY = top + child.getPaddingTop() + mLineMarginTop;        //画图       canvas.drawBitmap(mIcon, mLastX - (mIcon.getWidth() >> 1), mLastY, null);     }   }    private void drawBetweenLine(Canvas canvas) {     //从开始的点到最后的图标之间，画一条线     canvas.drawLine(mFirstX, mFirstY, mLastX, mLastY, mLinePaint);     for (int i = 0; i < getChildCount() - 1; i++) {       //画圆       int top = getChildAt(i).getTop();       int y = top + getChildAt(i).getPaddingTop() + mLineMarginTop;       canvas.drawCircle(mFirstX, y, mPointSize, mPointPaint);     }   }    public int getLineMarginLeft() {     return mLineMarginLeft;   }    public void setLineMarginLeft(int lineMarginLeft) {     this.mLineMarginLeft = lineMarginLeft;     invalidate();   } } 

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"   xmlns:app="http://schemas.android.com/apk/res-auto"   android:layout_width="match_parent"   android:layout_height="match_parent"   android:orientation="vertical">    <LinearLayout     android:layout_width="match_parent"     android:layout_height="50dp"     android:weightSum="2">      <Button       android:id="@+id/add_item"       android:layout_width="0dp"       android:layout_height="match_parent"       android:layout_weight="1"       android:text="add"/>      <Button       android:id="@+id/sub_item"       android:layout_width="0dp"       android:layout_height="match_parent"       android:layout_weight="1"       android:text="sub"/>   </LinearLayout>    <LinearLayout     android:layout_width="match_parent"     android:layout_height="wrap_content"     android:orientation="horizontal"     android:weightSum="2">      <Button       android:id="@+id/add_margin"       android:layout_width="0dp"       android:layout_weight="1"       android:layout_height="wrap_content"       android:text="+"/>      <Button       android:id="@+id/sub_margin"       android:layout_width="0dp"       android:layout_weight="1"       android:layout_height="wrap_content"       android:text="-"/>   </LinearLayout>    <TextView     android:id="@+id/current_margin"     android:layout_width="match_parent"     android:layout_height="40dp"     android:gravity="center"     android:text="current line margin left is 25dp"/>    <ScrollView     android:layout_width="match_parent"     android:layout_height="wrap_content"     android:scrollbars="none">      <com.jackie.timeline.TimelineLayout       android:id="@+id/timeline_layout"       android:layout_width="match_parent"       android:layout_height="wrap_content"       app:line_margin_left="25dp"       app:line_margin_top="8dp"       android:orientation="vertical"       android:background="@android:color/white">     </com.jackie.timeline.TimelineLayout>   </ScrollView> </LinearLayout> 

package com.jackie.timeline;  import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.view.LayoutInflater; import android.view.View; import android.widget.Button; import android.widget.TextView;  public class MainActivity extends AppCompatActivity implements View.OnClickListener {   private Button addItemButton;   private Button subItemButton;   private Button addMarginButton;   private Button subMarginButton;   private TextView mCurrentMargin;    private TimelineLayout mTimelineLayout;    @Override   protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.activity_main);      initView();   }    private void initView() {     addItemButton = (Button) findViewById(R.id.add_item);     subItemButton = (Button) findViewById(R.id.sub_item);     addMarginButton= (Button) findViewById(R.id.add_margin);     subMarginButton= (Button) findViewById(R.id.sub_margin);     mCurrentMargin= (TextView) findViewById(R.id.current_margin);     mTimelineLayout = (TimelineLayout) findViewById(R.id.timeline_layout);      addItemButton.setOnClickListener(this);     subItemButton.setOnClickListener(this);     addMarginButton.setOnClickListener(this);     subMarginButton.setOnClickListener(this);   }    private int index = 0;   private void addItem() {     View view = LayoutInflater.from(this).inflate(R.layout.item_timeline, mTimelineLayout, false);     ((TextView) view.findViewById(R.id.tv_action)).setText("步骤" + index);     ((TextView) view.findViewById(R.id.tv_action_time)).setText("2017年3月8日16:55:04");     ((TextView) view.findViewById(R.id.tv_action_status)).setText("完成");     mTimelineLayout.addView(view);     index++;   }    private void subItem() {     if (mTimelineLayout.getChildCount() > 0) {       mTimelineLayout.removeViews(mTimelineLayout.getChildCount() - 1, 1);       index--;     }   }    @Override   public void onClick(View v) {     switch (v.getId()){       case R.id.add_item:         addItem();         break;       case R.id.sub_item:         subItem();         break;       case R.id.add_margin:         int currentMargin = UIHelper.pxToDip(this, mTimelineLayout.getLineMarginLeft());         mTimelineLayout.setLineMarginLeft(UIHelper.dipToPx(this, ++currentMargin));         mCurrentMargin.setText("current line margin left is " + currentMargin + "dp");         break;       case R.id.sub_margin:         currentMargin = UIHelper.pxToDip(this, mTimelineLayout.getLineMarginLeft());         mTimelineLayout.setLineMarginLeft(UIHelper.dipToPx(this, --currentMargin));         mCurrentMargin.setText("current line margin left is " + currentMargin + "dp");         break;       default:         break;     }   } } 

<?xml version="1.0" encoding="utf-8"?> <RelativeLayout   xmlns:android="http://schemas.android.com/apk/res/android"   android:layout_width="match_parent"   android:layout_height="wrap_content"   android:paddingLeft="65dp"   android:paddingTop="20dp"   android:paddingRight="20dp"   android:paddingBottom="20dp">    <TextView     android:id="@+id/tv_action"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:textSize="14sp"     android:textColor="#1a1a1a"     android:text="测试一"/>    <TextView     android:id="@+id/tv_action_time"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:textSize="12sp"     android:textColor="#8e8e8e"     android:layout_below="@id/tv_action"     android:layout_marginTop="10dp"     android:text="2017年3月8日16:49:12"/>    <TextView     android:id="@+id/tv_action_status"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:textSize="14sp"     android:textColor="#3dd1a5"     android:layout_alignParentRight="true"     android:text="完成"/>  </RelativeLayout> 

package com.jackie.timeline;  import android.content.Context;  /**  * Created by Jackie on 2017/3/8.  */ public final class UIHelper {    private UIHelper() throws InstantiationException {     throw new InstantiationException("This class is not for instantiation");   }    /**    * dip转px    */   public static int dipToPx(Context context, float dip) {     return (int) (dip * context.getResources().getDisplayMetrics().density + 0.5f);   }    /**    * px转dip    */   public static int pxToDip(Context context, float pxValue) {     final float scale = context.getResources().getDisplayMetrics().density;     return (int) (pxValue / scale + 0.5f);   } }