package com.marshalchen.common.uimodule.showcaseview; import android.content.Context; import android.content.res.Resources; import android.graphics.Canvas; import android.graphics.Rect; import android.text.DynamicLayout; import android.text.Layout; import android.text.SpannableString; import android.text.TextPaint; import android.text.TextUtils; import android.text.style.TextAppearanceSpan; import com.marshalchen.ultimateandroiduicomponent.R; /** * Draws the text as required by the ShowcaseView */ class TextDrawer { private final TextPaint titlePaint; private final TextPaint textPaint; private final Context context; private final ShowcaseAreaCalculator calculator; private final float padding; private final float actionBarOffset; private CharSequence mTitle, mDetails; private float[] mBestTextPosition = new float[3]; private DynamicLayout mDynamicTitleLayout; private DynamicLayout mDynamicDetailLayout; private TextAppearanceSpan mTitleSpan; private TextAppearanceSpan mDetailSpan; private boolean hasRecalculated; public TextDrawer(Resources resources, ShowcaseAreaCalculator calculator, Context context) { padding = resources.getDimension(R.dimen.showcase_text_padding); actionBarOffset = resources.getDimension(R.dimen.showcase_action_bar_offset); this.calculator = calculator; this.context = context; titlePaint = new TextPaint(); titlePaint.setAntiAlias(true); textPaint = new TextPaint(); textPaint.setAntiAlias(true); } public void draw(Canvas canvas) { if (shouldDrawText()) { float[] textPosition = getBestTextPosition(); if (!TextUtils.isEmpty(mTitle)) { canvas.save(); if (hasRecalculated) { mDynamicTitleLayout = new DynamicLayout(mTitle, titlePaint, (int) textPosition[2], Layout.Alignment.ALIGN_NORMAL, 1.0f, 1.0f, true); } if (mDynamicTitleLayout != null) { canvas.translate(textPosition[0], textPosition[1]); mDynamicTitleLayout.draw(canvas); canvas.restore(); } } if (!TextUtils.isEmpty(mDetails)) { canvas.save(); if (hasRecalculated) { mDynamicDetailLayout = new DynamicLayout(mDetails, textPaint, (int) textPosition[2], Layout.Alignment.ALIGN_NORMAL, 1.2f, 1.0f, true); } float offsetForTitle = mDynamicTitleLayout != null ? mDynamicTitleLayout.getHeight() : 0; if (mDynamicDetailLayout != null) { canvas.translate(textPosition[0], textPosition[1] + offsetForTitle); mDynamicDetailLayout.draw(canvas); canvas.restore(); } } } hasRecalculated = false; } public void setContentText(CharSequence details) { if (details != null) { SpannableString ssbDetail = new SpannableString(details); ssbDetail.setSpan(mDetailSpan, 0, ssbDetail.length(), 0); mDetails = ssbDetail; } } public void setContentTitle(CharSequence title) { if (title != null) { SpannableString ssbTitle = new SpannableString(title); ssbTitle.setSpan(mTitleSpan, 0, ssbTitle.length(), 0); mTitle = ssbTitle; } } /** * Calculates the best place to position text * @param canvasW width of the screen * @param canvasH height of the screen * @param shouldCentreText */ public void calculateTextPosition(int canvasW, int canvasH, ShowcaseView showcaseView, boolean shouldCentreText) { Rect showcase = showcaseView.hasShowcaseView() ? calculator.getShowcaseRect() : new Rect(); int[] areas = new int[4]; //left, top, right, bottom areas[0] = showcase.left * canvasH; areas[1] = showcase.top * canvasW; areas[2] = (canvasW - showcase.right) * canvasH; areas[3] = (canvasH - showcase.bottom) * canvasW; int largest = 0; for(int i = 1; i < areas.length; i++) { if(areas[i] > areas[largest]) largest = i; } // Position text in largest area switch(largest) { case 0: mBestTextPosition[0] = padding; mBestTextPosition[1] = padding; mBestTextPosition[2] = showcase.left - 2 * padding; break; case 1: mBestTextPosition[0] = padding; mBestTextPosition[1] = padding + actionBarOffset; mBestTextPosition[2] = canvasW - 2 * padding; break; case 2: mBestTextPosition[0] = showcase.right + padding; mBestTextPosition[1] = padding; mBestTextPosition[2] = (canvasW - showcase.right) - 2 * padding; break; case 3: mBestTextPosition[0] = padding; mBestTextPosition[1] = showcase.bottom + padding; mBestTextPosition[2] = canvasW - 2 * padding; break; } if(shouldCentreText) { // Center text vertically or horizontally switch(largest) { case 0: case 2: mBestTextPosition[1] += canvasH / 4; break; case 1: case 3: mBestTextPosition[2] /= 2; mBestTextPosition[0] += canvasW / 4; break; } } else { // As text is not centered add actionbar padding if the text is left or right switch(largest) { case 0: case 2: mBestTextPosition[1] += actionBarOffset; break; } } hasRecalculated = true; } public void setTitleStyling(int styleId) { mTitleSpan = new TextAppearanceSpan(this.context, styleId); setContentTitle(mTitle); } public void setDetailStyling(int styleId) { mDetailSpan = new TextAppearanceSpan(this.context, styleId); setContentText(mDetails); } public CharSequence getContentTitle() { return mTitle; } public CharSequence getContentText() { return mDetails; } public float[] getBestTextPosition() { return mBestTextPosition; } public boolean shouldDrawText() { return !TextUtils.isEmpty(mTitle) || !TextUtils.isEmpty(mDetails); } }