今日头条加载进度条

    progressShow = true;    final ProgressDialog pd = new ProgressDialog(LoginActivity.this);    pd.setCanceledOnTouchOutside(false);    pd.setOnCancelListener(new DialogInterface.OnCancelListener() {        @Override        public void onCancel(DialogInterface dialog) {            Log.d(TAG, "EMClient.getInstance().onCancel");            progressShow = false;        }    });    pd.setMessage(getString(R.string.Is_landing));    pd.show();

源码

    /* * Copyright (C) 2007 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * *      http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */package android.app;import com.android.internal.R;import android.content.Context;import android.content.res.TypedArray;import android.graphics.drawable.Drawable;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.text.Spannable;import android.text.SpannableString;import android.text.style.StyleSpan;import android.view.LayoutInflater;import android.view.View;import android.widget.ProgressBar;import android.widget.TextView;import java.text.NumberFormat;/** * <p>A dialog showing a progress indicator and an optional text message or view. * Only a text message or a view can be used at the same time.</p> * <p>The dialog can be made cancelable on back key press.</p> * <p>The progress range is 0..10000.</p> */public class ProgressDialog extends AlertDialog {    /** Creates a ProgressDialog with a circular, spinning progress     * bar. This is the default.     */    public static final int STYLE_SPINNER = 0;    /** Creates a ProgressDialog with a horizontal progress bar.     */    public static final int STYLE_HORIZONTAL = 1;    private ProgressBar mProgress;    private TextView mMessageView;    private int mProgressStyle = STYLE_SPINNER;    private TextView mProgressNumber;    private String mProgressNumberFormat;    private TextView mProgressPercent;    private NumberFormat mProgressPercentFormat;    private int mMax;    private int mProgressVal;    private int mSecondaryProgressVal;    private int mIncrementBy;    private int mIncrementSecondaryBy;    private Drawable mProgressDrawable;    private Drawable mIndeterminateDrawable;    private CharSequence mMessage;    private boolean mIndeterminate;    private boolean mHasStarted;    private Handler mViewUpdateHandler;    public ProgressDialog(Context context) {        super(context);        initFormats();    }    public ProgressDialog(Context context, int theme) {        super(context, theme);        initFormats();    }    private void initFormats() {        mProgressNumberFormat = "%1d/%2d";        mProgressPercentFormat = NumberFormat.getPercentInstance();        mProgressPercentFormat.setMaximumFractionDigits(0);    }    public static ProgressDialog show(Context context, CharSequence title,            CharSequence message) {        return show(context, title, message, false);    }    public static ProgressDialog show(Context context, CharSequence title,            CharSequence message, boolean indeterminate) {        return show(context, title, message, indeterminate, false, null);    }    public static ProgressDialog show(Context context, CharSequence title,            CharSequence message, boolean indeterminate, boolean cancelable) {        return show(context, title, message, indeterminate, cancelable, null);    }    public static ProgressDialog show(Context context, CharSequence title,            CharSequence message, boolean indeterminate,            boolean cancelable, OnCancelListener cancelListener) {        ProgressDialog dialog = new ProgressDialog(context);        dialog.setTitle(title);        dialog.setMessage(message);        dialog.setIndeterminate(indeterminate);        dialog.setCancelable(cancelable);        dialog.setOnCancelListener(cancelListener);        dialog.show();        return dialog;    }    @Override    protected void onCreate(Bundle savedInstanceState) {        LayoutInflater inflater = LayoutInflater.from(mContext);        TypedArray a = mContext.obtainStyledAttributes(null,                com.android.internal.R.styleable.AlertDialog,                com.android.internal.R.attr.alertDialogStyle, 0);        if (mProgressStyle == STYLE_HORIZONTAL) {            /* Use a separate handler to update the text views as they             * must be updated on the same thread that created them.             */            mViewUpdateHandler = new Handler() {                @Override                public void handleMessage(Message msg) {                    super.handleMessage(msg);                    /* Update the number and percent */                    int progress = mProgress.getProgress();                    int max = mProgress.getMax();                    if (mProgressNumberFormat != null) {                        String format = mProgressNumberFormat;                        mProgressNumber.setText(String.format(format, progress, max));                    } else {                        mProgressNumber.setText("");                    }                    if (mProgressPercentFormat != null) {                        double percent = (double) progress / (double) max;                        SpannableString tmp = new SpannableString(mProgressPercentFormat.format(percent));                        tmp.setSpan(new StyleSpan(android.graphics.Typeface.BOLD),                                0, tmp.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);                        mProgressPercent.setText(tmp);                    } else {                        mProgressPercent.setText("");                    }                }            };            View view = inflater.inflate(a.getResourceId(                    com.android.internal.R.styleable.AlertDialog_horizontalProgressLayout,                    R.layout.alert_dialog_progress), null);            mProgress = (ProgressBar) view.findViewById(R.id.progress);            mProgressNumber = (TextView) view.findViewById(R.id.progress_number);            mProgressPercent = (TextView) view.findViewById(R.id.progress_percent);            setView(view);        } else {            View view = inflater.inflate(a.getResourceId(                    com.android.internal.R.styleable.AlertDialog_progressLayout,                    R.layout.progress_dialog), null);            mProgress = (ProgressBar) view.findViewById(R.id.progress);            mMessageView = (TextView) view.findViewById(R.id.message);            setView(view);        }        a.recycle();        if (mMax > 0) {            setMax(mMax);        }        if (mProgressVal > 0) {            setProgress(mProgressVal);        }        if (mSecondaryProgressVal > 0) {            setSecondaryProgress(mSecondaryProgressVal);        }        if (mIncrementBy > 0) {            incrementProgressBy(mIncrementBy);        }        if (mIncrementSecondaryBy > 0) {            incrementSecondaryProgressBy(mIncrementSecondaryBy);        }        if (mProgressDrawable != null) {            setProgressDrawable(mProgressDrawable);        }        if (mIndeterminateDrawable != null) {            setIndeterminateDrawable(mIndeterminateDrawable);        }        if (mMessage != null) {            setMessage(mMessage);        }        setIndeterminate(mIndeterminate);        onProgressChanged();        super.onCreate(savedInstanceState);    }    @Override    public void onStart() {        super.onStart();        mHasStarted = true;    }    @Override    protected void onStop() {        super.onStop();        mHasStarted = false;    }    public void setProgress(int value) {        if (mHasStarted) {            mProgress.setProgress(value);            onProgressChanged();        } else {            mProgressVal = value;        }    }    public void setSecondaryProgress(int secondaryProgress) {        if (mProgress != null) {            mProgress.setSecondaryProgress(secondaryProgress);            onProgressChanged();        } else {            mSecondaryProgressVal = secondaryProgress;        }    }    public int getProgress() {        if (mProgress != null) {            return mProgress.getProgress();        }        return mProgressVal;    }    public int getSecondaryProgress() {        if (mProgress != null) {            return mProgress.getSecondaryProgress();        }        return mSecondaryProgressVal;    }    public int getMax() {        if (mProgress != null) {            return mProgress.getMax();        }        return mMax;    }    public void setMax(int max) {        if (mProgress != null) {            mProgress.setMax(max);            onProgressChanged();        } else {            mMax = max;        }    }    public void incrementProgressBy(int diff) {        if (mProgress != null) {            mProgress.incrementProgressBy(diff);            onProgressChanged();        } else {            mIncrementBy += diff;        }    }    public void incrementSecondaryProgressBy(int diff) {        if (mProgress != null) {            mProgress.incrementSecondaryProgressBy(diff);            onProgressChanged();        } else {            mIncrementSecondaryBy += diff;        }    }    public void setProgressDrawable(Drawable d) {        if (mProgress != null) {            mProgress.setProgressDrawable(d);        } else {            mProgressDrawable = d;        }    }    public void setIndeterminateDrawable(Drawable d) {        if (mProgress != null) {            mProgress.setIndeterminateDrawable(d);        } else {            mIndeterminateDrawable = d;        }    }    public void setIndeterminate(boolean indeterminate) {        if (mProgress != null) {            mProgress.setIndeterminate(indeterminate);        } else {            mIndeterminate = indeterminate;        }    }    public boolean isIndeterminate() {        if (mProgress != null) {            return mProgress.isIndeterminate();        }        return mIndeterminate;    }    @Override    public void setMessage(CharSequence message) {        if (mProgress != null) {            if (mProgressStyle == STYLE_HORIZONTAL) {                super.setMessage(message);            } else {                mMessageView.setText(message);            }        } else {            mMessage = message;        }    }    public void setProgressStyle(int style) {        mProgressStyle = style;    }    /**     * Change the format of the small text showing current and maximum units     * of progress.  The default is "%1d/%2d".     * Should not be called during the number is progressing.     * @param format A string passed to {@link String#format String.format()};     * use "%1d" for the current number and "%2d" for the maximum.  If null,     * nothing will be shown.     */    public void setProgressNumberFormat(String format) {        mProgressNumberFormat = format;        onProgressChanged();    }    /**     * Change the format of the small text showing the percentage of progress.     * The default is     * {@link NumberFormat#getPercentInstance() NumberFormat.getPercentageInstnace().}     * Should not be called during the number is progressing.     * @param format An instance of a {@link NumberFormat} to generate the     * percentage text.  If null, nothing will be shown.     */    public void setProgressPercentFormat(NumberFormat format) {        mProgressPercentFormat = format;        onProgressChanged();    }    private void onProgressChanged() {        if (mProgressStyle == STYLE_HORIZONTAL) {            if (mViewUpdateHandler != null && !mViewUpdateHandler.hasMessages(0)) {                mViewUpdateHandler.sendEmptyMessage(0);            }        }    }}