編輯:關於Android編程
最近做項目,碰到如下的需求:ViewPager分頁,如果是6頁(包括6頁)就用圓點,如果是6頁以上就用進度條來切換。前面一種交互方法最常見,用小圓點來表示當前選中的頁面,這些小圓點稱為導航點,很多App都是這種實現方式。當用戶第一次安裝或升級應用時,都會利用導航頁面告訴用戶當前版本的主要亮點,一般情況下當行頁面有三部分組成,背景圖片,導航文字和滑動的原點,即下面的效果:
這裡就不作詳細的講解,大家可以參考我以前寫過的博客:
ViewPager實現圖片輪翻效果
今天來實現ViewPager進度條切換,主要邏輯如下:
MainActivity.java
package com.jackie.slidebarviewdemo.activity; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.widget.TextView; import com.jackie.slidebarviewdemo.R; import com.jackie.slidebarviewdemo.widget.SlideBarView; public class MainActivity extends AppCompatActivity { private SlideBarView mSlideBarView; private TextView mTextView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mSlideBarView = (SlideBarView) findViewById(R.id.slide_bar); mTextView = (TextView) findViewById(R.id.text_view); mSlideBarView.setTotalPage(80); mSlideBarView.setOnSlideChangeListener(new SlideBarView.OnSlideChangeListener() { @Override public void onSlideChange(int page) { mTextView.setText("當前是第" + page + "頁"); } }); } }
SlideBarView.java
package com.jackie.slidebarviewdemo.widget; import android.content.Context; import android.util.AttributeSet; import android.view.LayoutInflater; import android.view.MotionEvent; import android.view.View; import android.widget.LinearLayout; import android.widget.PopupWindow; import android.widget.RelativeLayout; import android.widget.TextView; import com.jackie.slidebarviewdemo.R; import com.jackie.slidebarviewdemo.utils.ConvertUtils; /** * Created by Jackie on 2017/1/17. */ public class SlideBarView extends RelativeLayout { private LayoutInflater mInflater; private RelativeLayout mSlideBarView; private View mSlideBarBlock; private PopupWindow mPopupWindow; private TextView mPopupText; private int mDp40; private String mBound = "no"; // no表示沒到邊界,left為到左邊界了,right表示到右邊界了 public interface OnSlideChangeListener { void onSlideChange(int page); } private OnSlideChangeListener mOnSlideChangeListener; public void setOnSlideChangeListener(OnSlideChangeListener onSlideChangeListener) { this.mOnSlideChangeListener = onSlideChangeListener; } public SlideBarView(Context context) { this(context, null); } public SlideBarView(Context context, AttributeSet attrs) { this(context, attrs, 0); } public SlideBarView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); init(context); initEvent(); } private void init(Context context) { mInflater = LayoutInflater.from(context); View slideBar = mInflater.inflate(R.layout.slide_bar, null); LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT); addView(slideBar, params); mSlideBarView = (RelativeLayout) slideBar.findViewById(R.id.slide_bar_view); mSlideBarBlock = slideBar.findViewById(R.id.slide_bar_block); mDp40 = ConvertUtils.dip2px(context, 40); } private void initEvent() { mSlideBarView.setOnTouchListener(new OnTouchListener() { int currentX = 0; int startX = 0; @Override public boolean onTouch(View v, MotionEvent event) { switch (event.getAction()) { case MotionEvent.ACTION_DOWN: currentX = (int) event.getX(); startX = (int) event.getX(); // 設置滑塊的滑動, 手指第一次點下去把滑塊放到手指上 int downLeft = currentX - mSlideBarBlock.getMeasuredWidth() / 2; int downTop = mSlideBarBlock.getTop(); int downRight = downLeft + mSlideBarBlock.getWidth(); int downBottom = mSlideBarBlock.getBottom(); //邊界檢測 if (downLeft < 0) { downLeft = 0; downRight = mSlideBarBlock.getMeasuredWidth(); } else if (downRight > mSlideBarView.getMeasuredWidth()) { downLeft = mSlideBarView.getMeasuredWidth() - mSlideBarBlock.getMeasuredWidth(); downRight = mSlideBarView.getMeasuredWidth(); } mSlideBarBlock.layout(downLeft, downTop, downRight, downBottom); break; case MotionEvent.ACTION_MOVE: currentX = (int) event.getX(); int currentPage = currentX * mTotalPage / mSlideBarView.getMeasuredWidth(); if (currentPage < 0) { currentPage = 0; } else if (currentPage > mTotalPage) { currentPage = mTotalPage; } // 設置滑塊的滑動 int moveLeft = currentX - mSlideBarBlock.getMeasuredWidth() / 2; int moveTop = mSlideBarBlock.getTop(); int moveRight = moveLeft + mSlideBarBlock.getMeasuredWidth(); int moveBottom = mSlideBarBlock.getBottom(); //邊界處理 if (moveLeft < 0) { mBound = "left"; moveLeft = 0; moveRight = mSlideBarBlock.getMeasuredWidth(); } else if (moveRight >= mSlideBarView.getMeasuredWidth()) { mBound = "right"; moveLeft = mSlideBarView.getMeasuredWidth() - mSlideBarBlock.getMeasuredWidth(); moveRight = mSlideBarView.getMeasuredWidth(); } else { mBound = "no"; } mSlideBarBlock.layout(moveLeft, moveTop, moveRight, moveBottom); startX = currentX; //設置popupWindow的彈出位置 if (mOnSlideChangeListener != null) { if (currentPage == mTotalPage) { //防止ViewPager越界 currentPage = mTotalPage - 1; } mOnSlideChangeListener.onSlideChange(currentPage); if (mPopupWindow != null) { mPopupText.setText(currentPage + ""); //設置PopupWindow的滑動 if (!mPopupWindow.isShowing()) { int[] location = new int[2]; mSlideBarView.getLocationInWindow(location); mPopupWindow.showAsDropDown(mSlideBarView, currentX, location[1] - mDp40); } else { if ("no".equals(mBound)) { int[] location = new int[2] ; mSlideBarView.getLocationInWindow(location); mPopupWindow.update(currentX, location[1] - mDp40, mPopupWindow.getWidth(), mPopupWindow.getHeight(), true); } } } } break; case MotionEvent.ACTION_UP: currentX = 0; startX = 0; mPopupWindow.dismiss(); break; } return true; } }); // 初始化PopupWindow View contentView = mInflater.inflate(R.layout.popup_window, null); mPopupText = (TextView) contentView.findViewById(R.id.popup_text); mPopupWindow = new PopupWindow(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT); mPopupWindow.setContentView(contentView); mPopupWindow.setOutsideTouchable(true); mPopupWindow.setBackgroundDrawable(getResources().getDrawable(R.mipmap.popup_window_bg)); mPopupWindow.setAnimationStyle(0); } int mTotalPage = 0; public void setTotalPage(int totalPage) { this.mTotalPage = totalPage; } }
相關的單位轉化工具,大家可以拷貝到自己的項目中直接使用。
ConvertUtils.java
package com.jackie.slidebarviewdemo.utils; import android.content.Context; public class ConvertUtils { public static int dip2px(Context context, float dpValue) { final float scale = context.getResources().getDisplayMetrics().density; return (int) (dpValue * scale + 0.5f); } public static int px2dip(Context context, float pxValue) { final float scale = context.getResources().getDisplayMetrics().density; return (int) (pxValue / scale + 0.5f); } public static int px2sp(Context context, float pxValue) { final float fontScale = context.getResources().getDisplayMetrics().scaledDensity; return (int) (pxValue / fontScale + 0.5f); } public static int sp2px(Context context, float spValue) { final float fontScale = context.getResources().getDisplayMetrics().scaledDensity; return (int) (spValue * fontScale + 0.5f); } }
自定義組合控件,然後實現相關的手勢,思路很清晰,代碼也很詳細,這裡就直接貼代碼了。
activity_main.xml
<?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="match_parent"> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_centerInParent="true" android:orientation="vertical"> <com.jackie.slidebarviewdemo.widget.SlideBarView android:id="@+id/slide_bar" android:layout_width="match_parent" android:layout_height="50dp" android:layout_marginLeft="20dp" android:layout_marginRight="20dp"/> <TextView android:id="@+id/text_view" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_horizontal" android:layout_marginTop="20dp" android:textColor="#000" android:textSize="20dp" android:text="當前是第0頁"/> </LinearLayout> </RelativeLayout>
activity_main.xml
<?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="match_parent"> <RelativeLayout android:id="@+id/slide_bar_view" android:layout_width="match_parent" android:layout_height="50dp"> <View android:layout_width="match_parent" android:layout_height="5dp" android:layout_centerInParent="true" android:background="@drawable/shape_slide_bar_bg"/> <View android:id="@+id/slide_bar_block" android:layout_width="20dp" android:layout_height="14dp" android:background="#b9b9b9" android:layout_centerVertical="true" /> </RelativeLayout> </RelativeLayout>
popup_window.xml
<?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="match_parent"> <RelativeLayout android:layout_width="30dp" android:layout_height="30dp"> <TextView android:id="@+id/popup_text" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textColor="#fff" android:textSize="16dp" android:gravity="center" android:layout_centerInParent="true" /> </RelativeLayout> </RelativeLayout>
附上相關的資源文件:
shape_slide_bar_bg.xml
<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle"> <solid android:color="#dcdcdc" /> <corners android:radius="1dp"/> </shape>
popup_window_bg.9.png
效果如下:
以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支持本站。
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