先给大家展示下效果图：

实现代码如下：

下面简单说下实现原理。

public class IndexBar extends LinearLayout implements View.OnTouchListener {

private static final String[] INDEXES = new String[]{"#", "A", "B", "C", "D", "E", "F", "G", "H",

"I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"};

private static final int TOUCHED_BACKGROUND_COLOR = 0x40000000;

private OnIndexChangedListener mListener;

public void setOnIndexChangedListener(OnIndexChangedListener listener) {

mListener = listener;

}

public IndexBar(Context context) {

this(context, null);

}

public IndexBar(Context context, AttributeSet attrs) {

this(context, attrs, 0);

}

public IndexBar(Context context, AttributeSet attrs, int defStyleAttr) {

super(context, attrs, defStyleAttr);

init(attrs);

}

private void init(AttributeSet attrs) {

TypedArray ta = getContext().obtainStyledAttributes(attrs, R.styleable.IndexBar);

float indexTextSize = ta.getDimension(R.styleable.IndexBar_indexTextSize, Utils.sp2px(getContext(), 12));

int indexTextColor = ta.getColor(R.styleable.IndexBar_indexTextColor, 0xFF616161);

ta.recycle();

setOrientation(VERTICAL);

setOnTouchListener(this);

for (String index : INDEXES) {

TextView text = new TextView(getContext());

text.setText(index);

text.setTextSize(TypedValue.COMPLEX_UNIT_PX, indexTextSize);

text.setTextColor(indexTextColor);

text.setGravity(Gravity.CENTER);

LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 0, 1);

text.setLayoutParams(params);

addView(text);

}

}

@Override

public boolean onTouch(View v, MotionEvent event) {

switch (event.getAction()) {

case MotionEvent.ACTION_DOWN:

setBackgroundColor(TOUCHED_BACKGROUND_COLOR);

handle(v, event);

return true;

case MotionEvent.ACTION_MOVE:

handle(v, event);

return true;

case MotionEvent.ACTION_UP:

setBackgroundColor(Color.TRANSPARENT);

handle(v, event);

return true;

}

return super.onTouchEvent(event);

}

private void handle(View v, MotionEvent event) {

int y = (int) event.getY();

int height = v.getHeight();

int position = INDEXES.length * y / height;

if (position < 0) {

position = 0;

} else if (position >= INDEXES.length) {

position = INDEXES.length - 1;

}

String index = INDEXES[position];

boolean showIndicator = event.getAction() != MotionEvent.ACTION_UP;

if (mListener != null) {

mListener.onIndexChanged(index, showIndicator);

}

}

public interface OnIndexChangedListener {

void onIndexChanged(String index, boolean showIndicator);

}

}

使用

public class CompanyActivity extends BaseActivity implements IndexBar.OnIndexChangedListener {

@Bind(R.id.lv_company)

ListView lvCompany;

@Bind(R.id.ib_indicator)

IndexBar ibIndicator;

@Bind(R.id.tv_indicator)

TextView tvIndicator;

private List mCompanyList = new ArrayList<>();

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_company);

// ...

}

@Override

public void onIndexChanged(String index, boolean showIndicator) {

int position = -1;

for (CompanyEntity company : mCompanyList) {

if (TextUtils.equals(company.getName(), index)) {

position = mCompanyList.indexOf(company);

break;

}

}

if (position != -1) {

lvCompany.setSelection(position);

}

tvIndicator.setText(index);

tvIndicator.setVisibility(showIndicator ? View.VISIBLE : View.GONE);

}

}

继承自LinearLayout，添加了26个字母索引TextView，当手指滑动时通知Activity更新界面。

核心是OnTouchListener，手指滑动的时候根据当前Y坐标计算出手指所在的索引位置，要注意临界值。

以上所述是小编给大家介绍的Android仿微信通讯录滑动快速定位功能，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对脚本之家网站的支持！